WO2025242868A1 - Phage composition - Google Patents

Abstract

The present invention relates to a composition comprising different isolated phages, wherein the phages comprise a nucleic acid being part of their genome, which hybridizes under stringent conditions to a particular signature sequence or its complementary sequence hereto comprising a nucleic acid sequence encoding their corresponding amino acid sequences, wherein the phages are capable of suppressing growth of Serratia marcescens, Klebsiella pneumoniae, and Pseudomonas aeruginosa such that OD600 is not higher than 0.5. The present invention also relates to a pharmaceutical composition comprising said composition, and to said composition or said pharmaceutical composition for use in therapy as well as for use in a method of treating or preventing a bacterial infection caused by at least any one of S. marcescens, K. pneumonia or P. aeruginosa. Additionally, the present invention relates to kits and to a method of preparing said composition comprising isolated phages and a composition comprising isolated phages obtainable or obtained by said method.

Description

PHAGE COMPOSITION

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application claims the benefit of priority of EP Patent Application No. 24177769.7 filed 23 May 2024, the content of which is hereby incorporated by reference in its entirety for all purposes.

FIELD OF THE INVENTION

[001] The present invention relates to a composition comprising different isolated phages, wherein the phages comprise a nucleic acid being part of their genome, which hybridizes under stringent conditions to a particular signature sequence or its complementary sequence hereto comprising a nucleic acid sequence encoding their corresponding amino acid sequences, wherein the phages are capable of suppressing growth of Serratia marcescens, Klebsiella pneumoniae, and Pseudomonas aeruginosa such that OD600 is not higher than 0.5. The present invention also relates to a pharmaceutical composition comprising said composition, and to said composition or said pharmaceutical composition for use in therapy as well as for use in a method of treating or preventing a bacterial infection caused by at least any one of S. marcescens, K. pneumonia or R aeruginosa. Additionally, the present invention relates to kits and to a method of preparing said composition comprising isolated phages and a composition comprising isolated phages obtainable or obtained by said method.

BACKGROUND OF THE INVENTION

[002] The spread of multi-resistant bacteria is a global human health threat, according to the World Health Organization (WHO)(Chandler, 2019, Palgrave Communications 5, 1-13). One way to tackle this threat is the development of new therapeutics as the development of novel antibiotics is both slow and expensive (Altamirano and Barr, 2019, Clinical Microbiology Reviews 32). The multiple-drug resistant species Serratia marcescens, Klebsiella pneumoniae, and Pseudomonas aeruginosa are of significant clinical concern. These bacteria often cause infections in people who have weakened immune systems, such as hospitalized or very sick patients. Serratia marcescens, Klebsiella pneumoniae, and Pseudomonas aeruginosa infections usually affect organ systems, which have a high content of fluid (e.g. peritoneal fluid, respiratory tract, urinary tract, cerebrospinal fluid etc.) leading to infections such as urinary tract infections (UTIs), respiratory tract infections (such as pneumonia), wound infections, bloodstream infections, and infections in immunocompromised individuals, and continuous ambulatory peritoneal dialysis. Moreover, bacterial pneumonia after viral infection is the leading cause of morbidity and mortality from infectious diseases worldwide, especially for the critical risk groups such as those with preexisting chronic lung diseases (Metersky et al., Int J Infect Dis (2012), 16: e321-331). A recent study of hospitalized COVID-19 patients in China found half of those who died acquired bacterial infections (Zhou et al., Lancet (2020), 395: 1054-1062). Furthermore, Serratia marcescens, Klebsiella pneumoniae, and Pseudomonas aeruginosa are often susceptible or resistant to many antibiotics, so that the threat level was escalated to urgent because of the emergence of easily spread resistance in Serratia marcescens, Klebsiella pneumoniae, and Pseudomonas aeruginosa and the lack of current antibiotics, and antibiotics in development, to treat these infections.

[003] Antimicrobial resistance (AMR) is a major threat to global health and global economies. Worldwide, infections by multiple-drug resistant bacteria are estimated to kill more than 700,000 people, including 25,000 cases in Europe and 23,000 cases in the US every year (Laximinarayan et al., The Lancet Infect Diseases (2013), 13: 1057-1098). Antimicrobial resistance also places a tremendous burden on healthcare systems and society, with an annual cost due to healthcare expenditures and productivity losses estimated by the European Commission at approximately €1.5 billion in the EU.

[004] To tackle this challenge, bacteriophages (also called phages), viruses that infect bacteria, can be employed to fight AMR as a complement to antibiotic therapy (Salmond et al., Nat Rev Micro (2015), 13: 777-786). Studies revealed that phages are the most abundant biological entities on earth, with ~10³¹ phages in total and about 10²³ phage infections per second. Phages are highly specific in their choice of bacterial hosts, mediated by specific receptor proteins, thus will cause no collateral damage to the microbial companions that form our microbiome, which is increasingly appreciated as essential to our health (Shreiner et al., Curr Op Gastroenterol (2015), 31 : 69-75). After over a billion years of co-evolutionary struggle with their bacterial hosts, phages have evolved highly diverse proteins that inhibit or ‘hijack’ bacterial metabolic processes to their own benefit.

[005] In sum, bacterial infections such as nosocomial pneumonia caused by AMR bacteria are generally a major concern.

[006] There is thus an ongoing need in the art to provide an alternative to antibiotics, such as a novel phage therapy for infections associated with AMR bacteria, such as Serratia marcescens, Klebsiella pneumoniae, and Pseudomonas aeruginosa. The technical problem underlying the present application is thus to comply with this need. The technical problem is solved by providing the embodiments reflected in the claims, described in the description and illustrated in the examples and figures that follow.

SUMMARY OF THE INVENTION

[007] The inventors successfully identified and characterized a composition comprising phages which have been isolated from samples inter alia by the proprietary high-throughput “viral tagging” as it is disclosed by WO2021/048257 incorporated by references herein and by classical phage isolation methods. The novel composition of the invention comprises phages which are against the antimicrobial resistance Serratia marcescens (short S. marcescens) bacteria, further comprising phages which are against the antimicrobial resistance Klebsiella pneumoniae (short K. pneumoniae) bacteria, and additionally comprising phages which are against the antimicrobial resistance Pseudomonas aeruginosa (short P. aeruginosa) bacteria so that such phages within the novel composition are capable of infecting S. marcescens, K. pneumoniae, and P. aeruginosa. This results in replication of phage genome within said host cell and lysis of such bacteria. Most importantly, by using the composition of the invention, the inventors were able to mitigate biofilm formation of the S. marcescens, K. pneumoniae, and P. aeruginosa strains, thus resulting in an efficient bacterial removal of the AMR S. marcescens, K. pneumoniae, and P. aeruginosa bacteria and therefore minimize the abovementioned problem with AMR. The isolated S. marcescens phages comprised within the composition of the invention hybridize with particular phage nucleic acid to (a) so called hook(s) which was/were designed by the inventors for the targeted S. marcescens phage isolation as explained in more detail below. The same also applies mutatis mutandis to the isolated K. pneumoniae and P. aeruginosa phages comprised within the novel composition of the invention.

[008] Accordingly, in a first aspect, the present invention comprises a composition comprising a) isolated first phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence hereto comprising a nucleic acid sequence encoding an amino acid sequence as depicted in at least any one selected from the group consisting of SEQ ID NOs: 1-10, wherein the phages are capable of suppressing growth of Serratia marcescens such that OD600 is not higher than 0.5, and wherein said nucleic acid being part of their genome comprises a nucleic acid sequence, which is at least 80% identical to the nucleic acid sequence encoding the amino acid sequence as depicted in at least any one selected from the group consisting of SEQ ID NOs: 1-10; b) isolated second phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence hereto comprising a nucleic acid sequence encoding an amino acid sequence as depicted in at least any one selected from the group consisting of SEQ ID NOs: 11-23, wherein the phages are capable of suppressing growth of Klebsiella pneumoniae such that OD600 is not higher than 0.5, and wherein said nucleic acid being part of their genome comprises a nucleic acid sequence, which is at least 80% identical to the nucleic acid sequence encoding the amino acid sequence as depicted in at least any one selected from the group consisting of SEQ ID NOs: 11-23; and c) isolated third phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence hereto comprising a nucleic acid sequence encoding an amino acid sequence as depicted in at least any one selected from the group consisting of SEQ ID NOs: 24-44, wherein the phages are capable of suppressing growth of Pseudomonas aeruginosa such that QD600 is not higher than 0.5, and wherein said nucleic acid being part of their genome comprises a nucleic acid sequence, which is at least 80% identical to the nucleic acid sequence encoding the amino acid sequence as depicted in at least any one selected from the group consisting of SEQ ID NOs: 24-44.

[009] Said signature sequence or its complementary sequence hereto comprising a nucleic acid sequence encoding an amino acid sequence as depicted in at least any one selected from the group consisting of SEQ ID NOs: 1-44, the isolated phages hybridize under stringent conditions to, are considered as the so called “hook(s)”. In a first step of designing such hooks, the phages comprised in a sample as defined elsewhere herein were labeled by the viral tagging procedure as defined by WO2021/048257, before target bacteria (S. marcescens, K. pneumoniae, and/or P. aeruginosa) were added into the samples comprising the labelled phages for phage isolation. After isolation of said S. marcescens, K. pneumoniae, and P. aeruginosa phages by flow cytometry and sorting, S. marcescens, K. pneumoniae, and P. aeruginosa bacteria were lysed to extract viral DNA as explained further in the Example section and the phage genome was then analyzed performing VT metagenomics sequencing and bioinformatics analysis (including protein clustering) as also described in the Examples. The genome of the isolated S. marcescens, K. pneumoniae, and P. aeruginosa phages, viral contigs generated by said viral tagging as defined by the Examples, and the S. marcescens, K. pneumoniae, and P. aeruginosa phage genomes from the NCBI RefSeq database were then used to create a gene catalogue, where the proteins of these genes were clustered into protein families and annotated. The most prevalent protein families within a viral cluster which was created by clustering said phage genome to genus level were used for designing said particular “hook(s)” the phages hybridize to and which hook(s) can then be applied for further targeted isolation of phages from a S. marcescens, K. pneumoniae, and P. aeruginosa phage colony (e.g. by applying qPCR wherein the defined hooks can be / were used as primers after viral tagging of phages comprised by a sample as defined elsewhere herein and infecting target bacteria S. marcescens, K. pneumoniae, and P. aeruginosa with such labeled phages within such sample as defined in more detail elsewhere herein). Such hooks - as can be seen below - may thus be used to fish out I isolate particular phages within a S. marcescens, K. pneumoniae, and P. aeruginosa phage colony which hybridize to said specific hook(s). The hybridization of the S. marcescens, phages to said defined hook(s) results in an isolation of divergent phages since each hook was designed for different phages, but which are all capable of infecting S. marcescens. The same applies mutatis mutandis to the K. pneumoniae and P. aeruginosa phages. For example the hook as defined by said signature sequence or its complementary sequence hereto comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 1 refers to a protein family of a major head protein which is one of the most abundant proteins within the S. marcescens phages which have been analysed by metagenomics sequencing. Meaning a targeted S. marcescens phage isolation using such particular hook allows to isolate the most divergent phages which are then comprised along with the equally isolated K. pneumoniae and P. aeruginosa phages in said composition of the invention.

[0010] In a second aspect, the present invention further encompasses a pharmaceutical composition comprising said composition as defined elsewhere herein.

[0011] The invention additionally comprises in a third aspect said composition as defined elsewhere herein or said pharmaceutical composition for use in therapy. In a fourth aspect, the invention envisages said composition or said pharmaceutical composition as defined elsewhere herein for use in a method of treating or preventing a bacterial infection caused by at least any one of S. marcescens, K. pneumoniae or P. aeruginosa in a subject, preferably wherein the subject also suffers from an infection with SARS-CoV-2.

[0012] In a fifth aspect, the present invention also comprises a kit comprising the composition as defined elsewhere herein or the pharmaceutical composition as defined elsewhere herein.

[0013] Accordingly, in a sixth aspect, the present invention also comprises a kit comprising i) a first nucleic acid sequence, which is at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, at least 98%, at least 99% or 100% identical to a nucleic acid sequence encoding an amino acid sequence as depicted in at least any one selected from the group consisting of SEQ ID NOs: 1-10, or a complementary sequence thereof; ii) a second nucleic acid sequence, which is at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, at least 98%, at least 99% or 100% identical to a nucleic acid sequence encoding an amino acid sequence as depicted in at least any one selected from the group consisting of SEQ ID NOs: 11-23, or a complementary sequence thereof; and iii) a third nucleic acid sequence, which is at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, at least 98%, at least 99% or 100% identical to a nucleic acid sequence encoding an amino acid sequence as depicted in at least any one selected from the group consisting of SEQ ID NOs: 24-44, or a complementary sequence thereof.

[0014] In a seventh aspect, the invention also encompasses a method of preparing a composition comprising isolated phages, the method comprising: targeted isolating of phages comprised in a provided sample, wherein i) the first phages comprise a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence hereto comprising a nucleic acid sequence encoding an amino acid sequence as depicted in at least any one selected from the group consisting of SEQ ID NOs: 1-10 and wherein the nucleic acid comprises a nucleic acid sequence, which is at least 80%, at least 90%, at least 95%, at least 98%, at least 99% or 100% identical to the nucleic acid sequence encoding the amino acid sequence as depicted in at least any one selected from the group consisting of SEQ ID NOs: 1-10; ii) the second phages comprise a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence hereto comprising a nucleic acid sequence encoding an amino acid sequence as depicted in at least any one selected from the group consisting of SEQ ID NOs: 11-23 and wherein the nucleic acid comprises a nucleic acid sequence, which is at least 80%, at least 90%, at least 95%, at least 98%, at least 99% or 00% identical to the nucleic acid sequence encoding the amino acid sequence as depicted in at least any one selected from the group consisting of SEQ ID NOs: 11-23; and iii) the third phages comprise a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence hereto comprising a nucleic acid sequence encoding an amino acid sequence as depicted in at least any one selected from the group consisting of SEQ ID NOs: 24- 44 and wherein the nucleic acid comprises a nucleic acid sequence, which is at least 80%, at least 90%, at least 95%, at least 98%, at least 99% or 100% identical to the nucleic acid sequence encoding the amino acid sequence as depicted in at least any one selected from the group consisting of SEQ ID NOs: 24-44.

[0015] Finally, the present invention envisages in an eighth aspect a composition comprising isolated phages obtainable or obtained by the method as defined above.

BRIEF DESCRIPTION OF THE FIGURES

[0016] Fig. 1 : A heatmap of the presence-absence matrix shows protein families (x-axis) in different viral clusters (y-axis). [0017] Fig. 2: Kinetic properties of Serratia marcescens phages. (A) to (C) In vitro kinetics of the HMGUsml, SMC100610, and SMC1400610 phages show high efficiency against their target bacteria.

[0018] Fig. 3: Kinetic properties of Klebsiella marsescens phages. (A) to (B) In vitro kinetics of the HMGUkpl and HMGUkp2 phages show high efficiency against their target bacteria.

[0019] Fig. 4: Kinetic properties of Pseudomonas aeruginosa phages. (A) to (B) In vitro kinetics of the HMGUpa3 and HMGUpa4 phages show high efficiency against their target bacteria.

[0020] Fig. 5: Morphological properties of the 5 selected phages. (A) Transmission electron microscopy of negatively stained S. marcescens HMGUsml phages. (B) Transmission electron microscopy of negatively stained K. pneumoniae HMGUkpl and HMGUkp2 phages. (C) Transmission electron microscopy of negatively stained P. aeruginosa HMGUpa3 and HMGUpa4 phages.

[0021] Fig. 6: Kinetic properties of the 5 selected phages as described in Figure 5. (A) to (C) In vitro kinetics of the phage cocktail showed highest efficiency against their target bacteria S. marcescens, K. pneumoniae and P. aeruginosa.

[0022] Fig. 7: Cocktail optimization in vivo. Treatment with the phage cocktail (also called “COVPHA cocktail” in the Figure) increased survival rates in larvae treated with P. aeruginosa + K. pneumoniae. Different MOIs are effective for the different bacteria used.

[0023] Fig. 8: Phage-antibiotic combinations. A) in vitro. B) in vivo. A combination of the phage cocktail and antibiotic gave better outcomes both in vitro and in vivo (Pa = P. aeruginosa; cocktail: the phage cocktail as defined herein; MRP: Meropenem).

DETAILED DESCRIPTION OF THE INVENTION

[0024] Although the present invention is described in detail below, it is to be understood that this invention is not limited to the particular methodologies, protocols and reagents described herein as these may vary. It is also to be understood that the terminology used herein is for the purpose of describing particular embodiments only, and is not intended to limit the scope of the present invention which will be limited only by the appended claims. Unless defined otherwise, all technical and scientific terms used herein have the same meanings as commonly understood by one of ordinary skill in the art. [0025] In the following, the elements of the present invention will be described. These elements are listed with specific embodiments, however, it should be understood that they may be combined in any manner and in any number to create additional embodiments. The variously described examples and preferred embodiments described throughout the specification should not be construed to limit the present invention to only the explicitly described embodiments. This description should be understood to support and encompass embodiments which combine the explicitly described embodiments with any number of the disclosed and/or preferred elements. Furthermore, any permutations and combinations of all elements described herein should be considered disclosed by the description of the present application unless the context indicates otherwise.

[0026] Throughout this specification and the claims which follow, unless the context requires otherwise, the word "comprise", and variations such as "comprises" and "comprising", will be understood to imply the inclusion of a stated member, integer or step or group of members, integers or steps but not the exclusion of any other member, integer or step or group of members, integers or steps although in some embodiments such other member, integer or step or group of members, integers or steps may be excluded, i.e. the subject-matter consists in the inclusion of a stated member, integer or step or group of members, integers or steps. When used herein the term “comprising” can be substituted with the term “containing” or “including” or sometimes when used herein with the term “having”. When used herein “consisting of' excludes any element, step, or ingredient not specified.

[0027] The terms "a" and "an" and "the" and similar reference used in the context of describing the invention (especially in the context of the claims) are to be construed to cover both the singular and the plural, unless otherwise indicated herein or clearly contradicted by context. Recitation of ranges of values herein is merely intended to serve as a shorthand method of referring individually to each separate value falling within the range. Unless otherwise indicated herein, each individual value is incorporated into the specification as if it were individually recited herein.

[0028] All methods described herein can be performed in any suitable order unless otherwise indicated herein or otherwise clearly contradicted by context. The use of any and all examples, or exemplary language (e.g., "such as"), provided herein is intended merely to better illustrate the invention and does not pose a limitation on the scope of the invention otherwise claimed. No language in the specification should be construed as indicating any non-claimed element essential to the practice of the invention.

[0029] Unless otherwise indicated, the term "at least" preceding a series of elements is to be understood to refer to every element in the series. The term “at least one” refers to one, two, three or more such as four, five, six, seven, eight, nine, ten and more. Those skilled in the art will recognize, or be able to ascertain using no more than routine experimentation, many equivalents to the specific embodiments of the invention described herein. Such equivalents are intended to be encompassed by the present invention.

[0030] The term “less than” or in turn “more than” or “below” does not include the concrete number.

[0031] The term "and/or" wherever used herein includes the meaning of "and", "or" and "all or any other combination of the elements connected by said term".

[0032] When used herein “consisting of" excludes any element, step, or ingredient not specified in the claim element. When used herein, "consisting essentially of' does not exclude materials or steps that do not materially affect the basic and novel characteristics of the claim.

[0033] The term “including” means “including but not limited to”. “Including” and “including but not limited to” are used interchangeably.

[0034] The term “about” means plus or minus 20%, preferably plus or minus 10%, more preferably plus or minus 5%, most preferably plus or minus 1 %.

[0035] Throughout the description and claims of this specification, the singular encompasses the plural unless the context otherwise requires. In particular, where the indefinite article is used, the specification is to be understood as contemplating plurality as well as singularity, unless the context requires otherwise.

[0036] It should be understood that this invention is not limited to the particular methodology, protocols, material, reagents, and substances, etc., described herein and as such can vary. The terminology used herein is for the purpose of describing particular embodiments only, and is not intended to limit the scope of the present invention, which is defined solely by the claims.

[0037] Several documents are cited throughout the text of this specification. Each of the documents cited herein (including all patents, patent applications, scientific publications, manufacturer's specifications, instructions, etc.), whether supra or infra, are hereby incorporated by reference in their entirety. Nothing herein is to be construed as an admission that the invention is not entitled to antedate such disclosure by virtue of prior invention. To the extent the material incorporated by reference contradicts or is inconsistent with this specification, the specification will supersede any such material. [0038] The content of all documents and patent documents cited herein is incorporated by reference in their entirety.

[0039] A better understanding of the present invention and of its advantages will be gained from the examples, offered for illustrative purposes only. The examples are not intended to limit the scope of the present invention in any way.

* * *

Composition

[0040] A “composition” comprising the phages which have been isolated as defined elsewhere herein, refers to any kind of composition which comprises these isolated phages, e.g. naturally- occurring I environmental samples, a nutritional composition, a cosmetic composition or the like. Said composition can be a liquid (preferably aqueous), a solid, a gel, a powder, a paste, an ointment, a capsule, a food product etc. Further comprised herein is a dried or frozen form of the composition as defined herein. Thus, said composition may be stored directly in liquid form for later use, stored in a frozen state and thawed prior to use, or prepared in dried form, such as a lyophilized, air-dried, or spray-dried form, for later reconstitution into a liquid form or other form prior to use. Thus, it is envisaged that a composition described herein may be stored by any method known to one of skill in the art. Non-limiting examples include cooling, freezing, lyophilizing, and spray drying the composition, wherein storage by cooling is preferred.

[0041] The composition of the invention comprising said isolated phages may further comprise one or more ingredients, by the way of illustration and not limitation, such as an excipient, a preservative, an ingestible support, a flavour, a solubilizer, a wetting agent, a sweetener, a colorant, a coating agent, or an antioxidant. The excipients of the composition may refer to diluents such as, e.g. water, saline, glycerol, ethanol, bacteriostatic water for injection (BWFI), Ringer's solution, dextrose solution, or aqueous solutions of salts and/or buffers etc. Thus, the composition of the present invention may further comprise at least one excipient as defined herein, preferably a buffer (pH buffering agent) as excipient. Furthermore, substances necessary for formulation purposes may be comprised in said composition as acceptable excipients such as emulsifying agents, stabilizing agent, and/or surfactants known to a person skilled in the art.

[0042] The term “buffer” or “pH buffering agent” as used herein, includes those agents that maintain the pH in a desired range. A buffer is an aqueous solution consisting of a mixture of a weak acid and its conjugate base or a weak base and its conjugated acid. It has the property that the pH of the solution changes very little when a small amount of a strong acid or base is added. Buffer solutions are used as a means of keeping pH at a nearly constant value in a wide variety of chemical applications. A buffer when applied in the composition of the invention preferably stabilizes the isolated phages. Preferably, as a buffer being further comprised by the composition of the present invention PBS or sodium bicarbonate buffer is used.

[0043] As used herein, the term “isolated” refers to a substance and/or entity that has been (1) separated from at least some of the components with which it was associated when initially produced (whether in nature and/or in an experimental setting), and/or (2) designed, produced, prepared, and/or manufactured by the hand of man. In the context of the present invention, the phages which are isolated may refer to the substance and/or entity separated from samples such as sewage water samples by applying at least any one of the defined hooks which have been explicitly designed I prepared by the inventors as explained above and in the Example section in more detail. Such “targeted phage isolation” (“hook isolation”) refers to applying viral tagging as defined in the Example section and as it is disclosed by WO2021/048257, followed by phage isolation methods as defined elsewhere herein and qPCR, where the already designed hook(s) are used as primers. In the context of the present invention, for the isolation of said labeled phages (after said viral tagging with a label) from a sample, Serratia marcescens, Klebsiella pneumoniae, and Pseudomonas aeruginosa bacterial cells as target bacteria are applied, whereby such labeled phages get into contact with said target cells by binding to receptors on the surface of such bacteria.

[0044] The term “nucleic acid molecule”, “nucleic acid strand” or the like can be used interchangeably with the term “nucleic acid” and means a polymer comprising one, two, or more nucleotides, e.g., single- or double stranded. Generally, nucleic acids may comprise inter alia DNA molecules, RNA molecules, oligonucleotide thiophosphates, substituted ribo-oligonucleotides or PNA molecules. Furthermore, such term may refer to DNA or RNA or hybrids thereof or any modification thereof that is known in the art (see, e.g., US 5525711 , US 471 1955, US 5792608 or EP 302175 for examples of modifications). The nucleic acid may be single- or double- stranded, linear or circular, natural or synthetic, and without any size limitation. For instance, the nucleic acid may be genomic DNA, cDNA, mitochondrial DNA, mRNA, antisense RNA, ribozymal RNA or a DNA encoding such RNAs or chimeroplasts (Gamper, Nucleic Acids Research, 2000, 28, 4332 - 4339). A nucleic acid described herein may also be a fragment of the nucleic acid. Particularly, such a fragment is a functional fragment. Examples for such functional fragments are nucleic acids which can serve as primers.

[0045] Such nucleic acid also comprising a nucleic acid sequence as known to a skilled person is part of the phage genome, and hybridizes under stringent conditions to a signature sequence or its complementary sequence as defined elsewhere herein. In this context, the term “being part of its genome” means that the nucleic acid (nucleic acid comprising a nucleic acid sequence) of the isolated phages belongs to the phage genome I is (integrated into) phage genome. Such phage genome (DNA or RNA), which refers to the totality of the genetic information of a phage, is comprised in the head of the phage and is then injected into the target bacteria as described herein for replication of its genome within said host cell. Thus, such nucleic acid can also be considered as “phage nucleic acid”. Such phage nucleic acid comprising a nucleic acid sequence may refer to a phage nucleic acid comprising a nucleic acid sequence, which is at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, at least 98%, at least 99% or 100% identical to the nucleic acid sequence encoding the amino acid sequence as depicted in at least any one selected from the group consisting of SEQ ID NOs: 1-10, identical to the nucleic acid sequence encoding the amino acid sequence as depicted in at least any one selected from the group consisting of SEQ ID NOs: 11-23, and/or identical to the nucleic acid sequence encoding the amino acid sequence as depicted in at least any one selected from the group consisting of SEQ ID NOs: 24-44; such as at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, at least 98%, at least 99% or 100% identical to the nucleic acid sequence encoding the amino acid sequence as depicted in SEQ ID NO: 1 ; at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, at least 98%, at least 99% or 100% identical to the nucleic acid sequence encoding the amino acid sequence as depicted in SEQ ID NO: 2; at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, at least 98%, at least 99% or 100% identical to the nucleic acid sequence encoding the amino acid sequence as depicted in SEQ ID NO: 3; at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, at least 98%, at least 99% or 100% identical to the nucleic acid sequence encoding the amino acid sequence as depicted in SEQ ID NO: 4; at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, at least 98%, at least 99% or 100% identical to the nucleic acid sequence encoding the amino acid sequence as depicted in SEQ ID NO: 5; at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, at least 98%, at least 99% or 100% identical to the nucleic acid sequence encoding the amino acid sequence as depicted in SEQ ID NO: 6, at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, at least 98%, at least 99% or 100% identical to the nucleic acid sequence encoding the amino acid sequence as depicted in SEQ ID NO: 7; at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, at least 98%, at least 99% or 100% identical to the nucleic acid sequence encoding the amino acid sequence as depicted in SEQ ID NO: 8; at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, at least 98%, at least 99% or 100% identical to the nucleic acid sequence encoding the amino acid sequence as depicted in SEQ ID NO: 9; and/or at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, at least 98%, at least 99% or 100% identical to the nucleic acid sequence encoding the amino acid sequence as depicted in SEQ ID NO: 10; such as at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, at least 98%, at least 99% or 100% identical to the nucleic acid sequence encoding the amino acid sequence as depicted in SEQ ID NO: 11 ; at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, at least 98%, at least 99% or 100% identical to the nucleic acid sequence encoding the amino acid sequence as depicted in SEQ ID NO: 12; at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, at least 98%, at least 99% or 100% identical to the nucleic acid sequence encoding the amino acid sequence as depicted in SEQ ID NO: 13; at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, at least 98%, at least 99% or 100% identical to the nucleic acid sequence encoding the amino acid sequence as depicted in SEQ ID NO: 14; at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, at least 98%, at least 99% or 100% identical to the nucleic acid sequence encoding the amino acid sequence as depicted in SEQ ID NO: 15; at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, at least 98%, at least 99% or 100% identical to the nucleic acid sequence encoding the amino acid sequence as depicted in SEQ ID NO: 16; at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, at least 98%, at least 99% or 100% identical to the nucleic acid sequence encoding the amino acid sequence as depicted in SEQ ID NO: 17; at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, at least 98%, at least 99% or 100% identical to the nucleic acid sequence encoding the amino acid sequence as depicted in SEQ ID NO: 18; at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, at least 98%, at least 99% or 100% identical to the nucleic acid sequence encoding the amino acid sequence as depicted in SEQ ID NO: 19; at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, at least 98%, at least 99% or 100% identical to the nucleic acid sequence encoding the amino acid sequence as depicted in SEQ ID NO: 20; at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, at least 98%, at least 99% or 100% identical to the nucleic acid sequence encoding the amino acid sequence as depicted in SEQ ID NO: 21 ; at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, at least 98%, at least 99% or 100% identical to the nucleic acid sequence encoding the amino acid sequence as depicted in SEQ ID NO: 22; and/or at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, at least 98%, at least 99% or 100% identical to the nucleic acid sequence encoding the amino acid sequence as depicted in SEQ ID NO: 23; such as at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, at least 98%, at least 99% or 100% identical to the nucleic acid sequence encoding the amino acid sequence as depicted in SEQ ID NO: 24; at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, at least 98%, at least 99% or 100% identical to the nucleic acid sequence encoding the amino acid sequence as depicted in SEQ ID NO: 25; at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, at least 98%, at least 99% or 100% identical to the nucleic acid sequence encoding the amino acid sequence as depicted in SEQ ID NO: 26; at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, at least 98%, at least 99% or 100% identical to the nucleic acid sequence encoding the amino acid sequence as depicted in SEQ ID NO: 27; at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, at least 98%, at least 99% or 100% identical to the nucleic acid sequence encoding the amino acid sequence as depicted in SEQ ID NO: 28; at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, at least 98%, at least 99% or 100% identical to the nucleic acid sequence encoding the amino acid sequence as depicted in SEQ ID NO: 29; at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, at least 98%, at least 99% or 100% identical to the nucleic acid sequence encoding the amino acid sequence as depicted in SEQ ID NO: 30; at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, at least 98%, at least 99% or 100% identical to the nucleic acid sequence encoding the amino acid sequence as depicted in SEQ ID NO: 31 ; at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, at least 98%, at least 99% or 100% identical to the nucleic acid sequence encoding the amino acid sequence as depicted in SEQ ID NO: 32; at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, at least 98%, at least 99% or 100% identical to the nucleic acid sequence encoding the amino acid sequence as depicted in SEQ ID NO: 33; at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, at least 98%, at least 99% or 100% identical to the nucleic acid sequence encoding the amino acid sequence as depicted in SEQ ID NO: 34; at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, at least 98%, at least 99% or 100% identical to the nucleic acid sequence encoding the amino acid sequence as depicted in SEQ ID NO: 35; at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, at least 98%, at least 99% or 100% identical to the nucleic acid sequence encoding the amino acid sequence as depicted in SEQ ID NO: 36; at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, at least 98%, at least 99% or 100% identical to the nucleic acid sequence encoding the amino acid sequence as depicted in SEQ ID NO: 37; at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, at least 98%, at least 99% or 100% identical to the nucleic acid sequence encoding the amino acid sequence as depicted in SEQ ID NO: 38; at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, at least 98%, at least 99% or 100% identical to the nucleic acid sequence encoding the amino acid sequence as depicted in SEQ ID NO: 39; at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, at least 98%, at least 99% or 100% identical to the nucleic acid sequence encoding the amino acid sequence as depicted in SEQ ID NO: 40; at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, at least 98%, at least 99% or 100% identical to the nucleic acid sequence encoding the amino acid sequence as depicted in SEQ ID NO: 41 ; at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, at least 98%, at least 99% or 100% identical to the nucleic acid sequence encoding the amino acid sequence as depicted in SEQ ID NO: 42; at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, at least 98%, at least 99% or 100% identical to the nucleic acid sequence encoding the amino acid sequence as depicted in SEQ ID NO: 43; and/or at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, at least 98%, at least 99% or 100% identical to the nucleic acid sequence encoding the amino acid sequence as depicted in SEQ ID NO: 44.

[0046] The term “nucleotide sequence” as known to a person skilled in the art can also be used interchangeably with the term “nucleic acid sequence”. [0047] By "identity" or “sequence identity” is meant a property of sequences that measures their similarity or relationship. The term "sequence identity" or "identity" as used in the present invention means the percentage of pair-wise identical residues - following (homology) alignment of a sequence - in the present invention the phage nucleic acid sequence - with a sequence in question (the nucleic acid sequence encoding the amino acid sequence as depicted in at least any one selected from the group consisting of SEQ ID NOs: 1-10, the nucleic acid sequence encoding the amino acid sequence as depicted in at least any one selected from the group consisting of SEQ ID NOs: 11-23 and/or the nucleic acid sequence encoding the amino acid sequence as depicted in at least any one selected from the group consisting of SEQ ID NOs: 24- 44 with respect to the number of residues in the longer of these two sequences. Identity is measured by dividing the number of identical residues by the total number of residues and multiplying the product by 100. The percentage of sequence identity can, for example, be determined herein using the program BLASTP, version blastp 2.2.5 (November 16, 2002; cf. Altschul, S. F. et al. (1997) Nucl. Acids Res.25, 3389-3402).

[0048] The level of identity between two or more sequences (e.g., nucleic acid sequences or amino acid sequences) can be easily determined by methods known in the art, e.g., by BLAST analysis. Generally, in context with the present invention, if two sequences (e.g., nucleic acid sequences or amino acid sequences) to be compared by, e.g., sequence comparisons differ in identity, then the term "identity" may refer to the shorter sequence and that part of the longer sequence that matches said shorter sequence. Therefore, when the sequences which are compared do not have the same length, the degree of identity may preferably either refer to the percentage of nucleotide residues in the shorter sequence which are identical to nucleotide residues in the longer sequence or to the percentage of nucleotides in the longer sequence which are identical to nucleotide sequence in the shorter sequence. In this context, the skilled person is readily in the position to determine that part of a longer sequence that matches the shorter sequence. Furthermore, as used herein, identity levels of nucleic acid sequences or amino acid sequences may refer to the entire length of the respective sequence and is preferably assessed pair-wise, wherein each gap is to be counted as one mismatch. These definitions for sequence comparisons (e.g., establishment of "identity" values) are to be applied for all sequences described and disclosed herein.

[0049] Moreover, the term “identity” or “identical” as used herein means that there is a functional and/or structural equivalence between the corresponding sequences. Nucleic acid/amino acid sequences having the given identity levels to the herein-described particular nucleic acid/amino acid sequences may represent derivatives/variants of these sequences which, preferably, have the same biological function. They may be either naturally occurring variations, for instance sequences from other varieties, species, etc., or mutations, and said mutations may have formed naturally or may have been produced by deliberate mutagenesis. Furthermore, the variations may be synthetically produced sequences. The variants may be naturally occurring variants or synthetically produced variants, or variants produced by recombinant DNA techniques. Deviations from the above-described nucleic acid sequences may have been produced, e.g., by deletion, substitution, addition, insertion and/or recombination. The term "addition" refers to adding a nucleic acid residue/amino acid to the beginning or end of the given sequence, whereas "insertion" refers to inserting a nucleic acid residue/amino acid within a given sequence. The term "deletion" refers to deleting or removal of a nucleic acid residue or amino acid residue in a given sequence. The term "substitution" refers to the replacement of a nucleic acid residue/amino acid residue in a given sequence. Again, these definitions as used here apply, mutatis mutandis, for all sequences provided and described herein.

[0050] The term “hybridize” “hybridizing” refers to “bind” or “binding”, or “being complementary to”, e.g. with regard to the phages to be isolated from a Serratia marcescens phage colony, a Klebsiella pneumoniae phage colony, and a Pseudomonas aeruginosa phage colony by applying such hook(s) as defined herein where the phages hybridize to. In detail, the nucleic acid (comprising a nucleic acid sequence) within the phage genome binds to the defined hook, namely a signature sequence or its complementary sequence comprising a nucleic acid sequence which encodes an amino acid sequence as depicted in at least any one of SEQ ID NOs: 1-10, as depicted in at least any one of SEQ ID NOs: 11-23, and/or as depicted in at least any one of SEQ ID NOs: 24-44. Such term may also comprise hybridizing to at least a portion of the signature sequence or its complementary sequence as defined herein, which means that said phage nucleic acid hybridizes or is complementary to at least about 3, 4, 5, 6, 7, 8, 9, 20, 11 , 12, 13, 14 or 15 (preferably consecutive) nucleotides of the nucleotide sequence comprised by the signature sequence or its complementary sequence encoding at least any one of the amino acid sequence as shown in SEQ ID NOs: 1-10, and/or encoding at least any one of the amino acid sequence as shown in SEQ ID NOs: 11-23, and/or encoding at least any one of the amino acid sequence as shown in SEQ ID NOs: 24-44. That is, for example, in accordance with this embodiment of the present invention, the nucleic acid being part of the phage genome hybridizes under stringent conditions to at least about 3, 4, 5, 6, 7, 8, 9, 20, 11 , 12, 13, 14 or 15 (preferably consecutive) nucleotides of the nucleotide sequence comprised by the signature sequence or its complementary sequence encoding an amino acid sequence as depicted in SEQ ID NO: 1 ; the phage nucleic acid being part of the phage genome hybridizes under stringent conditions to at least about 3, 4, 5, 6, 7, 8, 9, 20, 11 , 12, 13, 14 or 15 (preferably consecutive) nucleotides of the nucleotide sequence comprised by the signature sequence or its complementary sequence encoding an amino acid sequence as depicted in SEQ ID NO: 2; the phage nucleic acid being part of the phage genome hybridizes under stringent conditions to at least about 3, 4, 5, 6, 7, 8, 9, 20, 11 , 12, 13, 14 or 15 (preferably consecutive) nucleotides of the nucleotide sequence comprised by the signature sequence or its complementary sequence encoding an amino acid sequence as depicted in SEQ ID NO: 3; the phage nucleic acid being part of the phage genome hybridizes under stringent conditions to at least about 3, 4, 5, 6, 7, 8, 9, 20, 11 , 12, 13, 14 or 15 (preferably consecutive) nucleotides of the nucleotide sequence comprised by the signature sequence or its complementary sequence encoding an amino acid sequence as depicted in SEQ ID NO: 4; the phage nucleic acid being part of the phage genome hybridizes under stringent conditions to at least about 3, 4, 5, 6, 7, 8, 9, 20, 11 , 12, 13, 14 or 15 (preferably consecutive) nucleotides of the nucleotide sequence comprised by the signature sequence or its complementary sequence encoding an amino acid sequence as depicted in SEQ ID NO: 5; the phage nucleic acid being part of the phage genome hybridizes under stringent conditions to at least about 3, 4, 5, 6, 7, 8, 9, 20, 11 , 12, 13, 14 or 15 (preferably consecutive) nucleotides of the nucleotide sequence comprised by the signature sequence or its complementary sequence encoding an amino acid sequence as depicted in SEQ ID NO: 6; the phage nucleic acid being part of the phage genome hybridizes under stringent conditions to at least about 3, 4, 5, 6, 7, 8, 9, 20, 11 , 12, 13, 14 or 15 (preferably consecutive) nucleotides of the nucleotide sequence comprised by the signature sequence or its complementary sequence encoding an amino acid sequence as depicted in SEQ ID NO: 7; the phage nucleic acid being part of the phage genome hybridizes under stringent conditions to at least about 3, 4, 5, 6, 7, 8, 9, 20, 11 , 12, 13, 14 or 15 (preferably consecutive) nucleotides of the nucleotide sequence comprised by the signature sequence or its complementary sequence encoding an amino acid sequence as depicted in SEQ ID NO: 8; the phage nucleic acid being part of the phage genome hybridizes under stringent conditions to at least about 3, 4, 5, 6, 7, 8, 9, 20, 11 , 12, 13, 14 or 15 (preferably consecutive) nucleotides of the nucleotide sequence comprised by the signature sequence or its complementary sequence encoding an amino acid sequence as depicted in SEQ ID NO: 9; and/or the phage nucleic acid being part of the phage genome hybridizes under stringent conditions to at least about 3, 4, 5, 6, 7, 8, 9, 20, 11 , 12, 13, 14 or 15 (preferably consecutive) nucleotides of the nucleotide sequence comprised by the signature sequence or its complementary sequence encoding an amino acid sequence as depicted in SEQ ID NO: 10; the phage nucleic acid being part of the phage genome hybridizes under stringent conditions to at least about 3, 4, 5, 6, 7, 8, 9, 20, 11 , 12, 13, 14 or 15 (preferably consecutive) nucleotides of the nucleotide sequence comprised by the signature sequence or its complementary sequence encoding an amino acid sequence as depicted in SEQ ID NO: 11 ; the phage nucleic acid being part of the phage genome hybridizes under stringent conditions to at least about 3, 4, 5, 6, 7, 8, 9, 20, 11 , 12, 13, 14 or 15 (preferably consecutive) nucleotides of the nucleotide sequence comprised by the signature sequence or its complementary sequence encoding an amino acid sequence as depicted in SEQ ID NO: 12; the phage nucleic acid being part of the phage genome hybridizes under stringent conditions to at least about 3, 4, 5, 6, 7, 8, 9, 20, 11 , 12, 13, 14 or 15 (preferably consecutive) nucleotides of the nucleotide sequence comprised by the signature sequence or its complementary sequence encoding an amino acid sequence as depicted in SEQ ID NO: 13; the phage nucleic acid being part of the phage genome hybridizes under stringent conditions to at least about 3, 4, 5, 6, 7, 8, 9, 20, 11 , 12, 13, 14 or 15 (preferably consecutive) nucleotides of the nucleotide sequence comprised by the signature sequence or its complementary sequence encoding an amino acid sequence as depicted in SEQ ID NO: 14; the phage nucleic acid being part of the phage genome hybridizes under stringent conditions to at least about 3, 4, 5, 6, 7, 8, 9, 20, 11 , 12, 13, 14 or 15 (preferably consecutive) nucleotides of the nucleotide sequence comprised by the signature sequence or its complementary sequence encoding an amino acid sequence as depicted in SEQ ID NO: 15; the phage nucleic acid being part of the phage genome hybridizes under stringent conditions to at least about 3, 4, 5, 6, 7, 8, 9, 20, 11 , 12, 13, 14 or 15 (preferably consecutive) nucleotides of the nucleotide sequence comprised by the signature sequence or its complementary sequence encoding an amino acid sequence as depicted in SEQ ID NO: 16; the phage nucleic acid being part of the phage genome hybridizes under stringent conditions to at least about 3, 4, 5, 6, 7, 8, 9, 20, 11 , 12, 13, 14 or 15 (preferably consecutive) nucleotides of the nucleotide sequence comprised by the signature sequence or its complementary sequence encoding an amino acid sequence as depicted in SEQ ID NO: 17; the phage nucleic acid being part of the phage genome hybridizes under stringent conditions to at least about 3, 4, 5, 6, 7, 8, 9, 20, 11 , 12, 13, 14 or 15 (preferably consecutive) nucleotides of the nucleotide sequence comprised by the signature sequence or its complementary sequence encoding an amino acid sequence as depicted in SEQ ID NO: 18; the phage nucleic acid being part of the phage genome hybridizes under stringent conditions to at least about 3, 4, 5, 6, 7, 8, 9, 20, 11 , 12, 13, 14 or 15 (preferably consecutive) nucleotides of the nucleotide sequence comprised by the signature sequence or its complementary sequence encoding an amino acid sequence as depicted in SEQ ID NO: 19; the phage nucleic acid being part of the phage genome hybridizes under stringent conditions to at least about 3, 4, 5, 6, 7, 8, 9, 20, 11 , 12, 13, 14 or 15 (preferably consecutive) nucleotides of the nucleotide sequence comprised by the signature sequence or its complementary sequence encoding an amino acid sequence as depicted in SEQ ID NO: 20; the phage nucleic acid being part of the phage genome hybridizes under stringent conditions to at least about 3, 4, 5, 6, 7, 8, 9, 20, 11 , 12, 13, 14 or 15 (preferably consecutive) nucleotides of the nucleotide sequence comprised by the signature sequence or its complementary sequence encoding an amino acid sequence as depicted in SEQ ID NO: 21 ; the phage nucleic acid being part of the phage genome hybridizes under stringent conditions to at least about 3, 4, 5, 6, 7, 8, 9, 20, 11 , 12, 13, 14 or 15 (preferably consecutive) nucleotides of the nucleotide sequence comprised by the signature sequence or its complementary sequence encoding an amino acid sequence as depicted in SEQ ID NO: 22 and/or the phage nucleic acid being part of the phage genome hybridizes under stringent conditions to at least about 3, 4, 5, 6, 7, 8, 9, 20, 11 , 12, 13, 14 or 15 (preferably consecutive) nucleotides of the nucleotide sequence comprised by the signature sequence or its complementary sequence encoding an amino acid sequence as depicted in SEQ ID NO: 23; the phage nucleic acid being part of the phage genome hybridizes under stringent conditions to at least about 3, 4, 5, 6, 7, 8, 9, 20, 11 , 12, 13, 14 or 15 (preferably consecutive) nucleotides of the nucleotide sequence comprised by the signature sequence or its complementary sequence encoding an amino acid sequence as depicted in SEQ ID NO: 24; the phage nucleic acid being part of the phage genome hybridizes under stringent conditions to at least about 3, 4, 5, 6, 7, 8, 9, 20, 11 , 12, 13, 14 or 15 (preferably consecutive) nucleotides of the nucleotide sequence comprised by the signature sequence or its complementary sequence encoding an amino acid sequence as depicted in SEQ ID NO: 25; the phage nucleic acid being part of the phage genome hybridizes under stringent conditions to at least about 3, 4, 5, 6, 7, 8, 9, 20, 11 , 12, 13, 14 or 15 (preferably consecutive) nucleotides of the nucleotide sequence comprised by the signature sequence or its complementary sequence encoding an amino acid sequence as depicted in SEQ ID NO: 26; the phage nucleic acid being part of the phage genome hybridizes under stringent conditions to at least about 3, 4, 5, 6, 7, 8, 9, 20, 11 , 12, 13, 14 or 15 (preferably consecutive) nucleotides of the nucleotide sequence comprised by the signature sequence or its complementary sequence encoding an amino acid sequence as depicted in SEQ ID NO: 27; the phage nucleic acid being part of the phage genome hybridizes under stringent conditions to at least about 3, 4, 5, 6, 7, 8, 9, 20, 11 , 12, 13, 14 or 15 (preferably consecutive) nucleotides of the nucleotide sequence comprised by the signature sequence or its complementary sequence encoding an amino acid sequence as depicted in SEQ ID NO: 28; the phage nucleic acid being part of the phage genome hybridizes under stringent conditions to at least about 3, 4, 5, 6, 7, 8, 9, 20, 11 , 12, 13, 14 or 15 (preferably consecutive) nucleotides of the nucleotide sequence comprised by the signature sequence or its complementary sequence encoding an amino acid sequence as depicted in SEQ ID NO: 29; the phage nucleic acid being part of the phage genome hybridizes under stringent conditions to at least about 3, 4, 5, 6, 7, 8, 9, 20, 11 , 12, 13, 14 or 15 (preferably consecutive) nucleotides of the nucleotide sequence comprised by the signature sequence or its complementary sequence encoding an amino acid sequence as depicted in SEQ ID NO: 30; the phage nucleic acid being part of the phage genome hybridizes under stringent conditions to at least about 3, 4, 5, 6, 7, 8, 9, 20, 11 , 12, 13, 14 or 15 (preferably consecutive) nucleotides of the nucleotide sequence comprised by the signature sequence or its complementary sequence encoding an amino acid sequence as depicted in SEQ ID NO: 31 ; the phage nucleic acid being part of the phage genome hybridizes under stringent conditions to at least about 3, 4, 5, 6, 7, 8, 9, 20, 11 , 12, 13, 14 or 15 (preferably consecutive) nucleotides of the nucleotide sequence comprised by the signature sequence or its complementary sequence encoding an amino acid sequence as depicted in SEQ ID NO: 32; the phage nucleic acid being part of the phage genome hybridizes under stringent conditions to at least about 3, 4, 5, 6, 7, 8, 9, 20, 11 , 12, 13, 14 or 15 (preferably consecutive) nucleotides of the nucleotide sequence comprised by the signature sequence or its complementary sequence encoding an amino acid sequence as depicted in SEQ ID NO: 33; the phage nucleic acid being part of the phage genome hybridizes under stringent conditions to at least about 3, 4, 5, 6, 7, 8, 9, 20, 11 , 12, 13, 14 or 15 (preferably consecutive) nucleotides of the nucleotide sequence comprised by the signature sequence or its complementary sequence encoding an amino acid sequence as depicted in SEQ ID NO: 34; the phage nucleic acid being part of the phage genome hybridizes under stringent conditions to at least about 3, 4, 5, 6, 7, 8, 9, 20, 11 , 12, 13, 14 or 15 (preferably consecutive) nucleotides of the nucleotide sequence comprised by the signature sequence or its complementary sequence encoding an amino acid sequence as depicted in SEQ ID NO: 35; the phage nucleic acid being part of the phage genome hybridizes under stringent conditions to at least about 3, 4, 5, 6, 7, 8, 9, 20, 11 , 12, 13, 14 or 15 (preferably consecutive) nucleotides of the nucleotide sequence comprised by the signature sequence or its complementary sequence encoding an amino acid sequence as depicted in SEQ ID NO: 36; the phage nucleic acid being part of the phage genome hybridizes under stringent conditions to at least about 3, 4, 5, 6, 7, 8, 9, 20, 11 , 12, 13, 14 or 15 (preferably consecutive) nucleotides of the nucleotide sequence comprised by the signature sequence or its complementary sequence encoding an amino acid sequence as depicted in SEQ ID NO: 37; the phage nucleic acid being part of the phage genome hybridizes under stringent conditions to at least about 3, 4, 5, 6, 7, 8, 9, 20, 11 , 12, 13, 14 or 15 (preferably consecutive) nucleotides of the nucleotide sequence comprised by the signature sequence or its complementary sequence encoding an amino acid sequence as depicted in SEQ ID NO: 38; the phage nucleic acid being part of the phage genome hybridizes under stringent conditions to at least about 3, 4, 5, 6, 7, 8, 9, 20, 11 , 12, 13, 14 or 15 (preferably consecutive) nucleotides of the nucleotide sequence comprised by the signature sequence or its complementary sequence encoding an amino acid sequence as depicted in SEQ ID NO: 39; the phage nucleic acid being part of the phage genome hybridizes under stringent conditions to at least about 3, 4, 5, 6, 7, 8, 9, 20, 11 , 12, 13, 14 or 15 (preferably consecutive) nucleotides of the nucleotide sequence comprised by the signature sequence or its complementary sequence encoding an amino acid sequence as depicted in SEQ ID NO: 40; the phage nucleic acid being part of the phage genome hybridizes under stringent conditions to at least about 3, 4, 5, 6, 7, 8, 9, 20, 11 , 12, 13, 14 or 15 (preferably consecutive) nucleotides of the nucleotide sequence comprised by the signature sequence or its complementary sequence encoding an amino acid sequence as depicted in SEQ ID NO: 41 ; the phage nucleic acid being part of the phage genome hybridizes under stringent conditions to at least about 3, 4, 5, 6, 7, 8, 9, 20, 11 , 12, 13, 14 or 15 (preferably consecutive) nucleotides of the nucleotide sequence comprised by the signature sequence or its complementary sequence encoding an amino acid sequence as depicted in SEQ ID NO: 42; the phage nucleic acid being part of the phage genome hybridizes under stringent conditions to at least about 3, 4, 5, 6, 7, 8, 9, 20, 11 , 12, 13, 14 or 15 (preferably consecutive) nucleotides of the nucleotide sequence comprised by the signature sequence or its complementary sequence encoding an amino acid sequence as depicted in SEQ ID NO: 43; and/or the phage nucleic acid being part of the phage genome hybridizes under stringent conditions to at least about 3, 4, 5, 6, 7, 8, 9, 20, 11 , 12, 13, 14 or 15 (preferably consecutive) nucleotides of the nucleotide sequence comprised by the signature sequence or its complementary sequence encoding an amino acid sequence as depicted in SEQ ID NO: 44.

[0051] The term "hybridization", “hybridizing” or "hybridizes" as used herein in context of nucleic acid molecules/DNA or RNA sequences may relate to hybridizations under stringent or nonstringent conditions. If not further specified, the conditions are preferably stringent. Said hybridization conditions may be established according to conventional protocols described, for example, in Sambrook, Russell "Molecular Cloning, A Laboratory Manual", Cold Spring Harbor Laboratory, N. Y. (2001); Current Protocols in Molecular Biology, Update May 9, 2012, Print ISSN: 1934-3639, Online ISSN: 1934-3647; Ausubel, "Current Protocols in Molecular Biology", Green Publishing Associates and Wiley Interscience, N. Y. (1989), or Higgins and Hames (Eds.) "Nucleic acid hybridization, a practical approach" IRL Press Oxford, Washington DC, (1985). The setting of conditions is well known within the skill of the artisan and can be determined according to protocols described in the art. Thus, the detection of only specifically hybridizing sequences will usually require stringent hybridization and washing conditions such as 0.1 x SSC, 0.1 % SDS at 65 °C. Non-stringent hybridization conditions for the detection of homologous or not exactly complementary sequences may be set at 6 x SSC, 1 % SDS at 65 °C. As is well known, the length of the probe and the composition of the nucleic acid to be determined constitute further parameters of the hybridization conditions. Variations in the above conditions may be accomplished through the inclusion and/or substitution of alternate blocking reagents used to suppress background in hybridization experiments. Typical blocking reagents include Denhardt's reagent, BLOTTO, heparin, denatured salmon sperm DNA, and commercially available proprietary formulations. The inclusion of specific blocking reagents may require modification of the hybridization conditions described above, due to problems with compatibility.

[0052] Hybridizing nucleic acid molecules also comprise fragments of the above described molecules. Such fragments may represent nucleic acid molecules which encode for a functional hook as described herein or a functional fragment thereof. Furthermore, nucleic acid molecules which hybridize with any of the aforementioned nucleic acid molecules also include complementary fragments, derivatives and variants of these molecules. Additionally, a hybridization complex refers to a complex between two nucleic acid sequences by virtue of the formation of hydrogen bonds between complementary G and C bases and between complementary A and T bases; these hydrogen bonds may be further stabilized by base stacking interactions. The two complementary nucleic acid sequences hydrogen bond in an antiparallel configuration. A hybridization complex may be formed in solution (e.g., Cot or Rot analysis) or between one nucleic acid sequence present in solution and another nucleic acid sequence immobilized on a solid support (e.g., membranes, filters, chips, pins or glass slides to which, e.g., cells have been fixed). The terms complementary or complementarity refer to the natural binding of polynucleotides under permissive salt and temperature conditions by base-pairing. For example, the sequence "A-G-T" binds to the complementary sequence "T-C-A". Complementarity between two single-stranded molecules may be "partial", in which only some of the nucleic acids bind, or it may be complete when total complementarity exists between single-stranded molecules. The degree of complementarity between nucleic acid strands has significant effects on the efficiency and strength of hybridization between nucleic acid strands. This is of particular importance in amplification reactions, which depend upon binding between nucleic acids strands. The term "hybridizing nucleic acids I sequences" preferably refers to sequences which display a sequence identity of at least 60%, more preferably at least 65%, more preferably at least 70%, more preferably at least 75%, more preferably at least 80%, more preferably at least 85%, more preferably at least 90%, more preferably at least 95%, more preferably at least 96%, more preferably at least 97%, more preferably at least 98% more preferably at least 99%, more preferably at least 99.5%, and most preferably 100% identity with a nucleic acid I nucleic acid sequence as described herein, e.g. “hybridize” or “hybridizing” as used herein preferably refers to a nucleic acid being part of its genome of the isolated phages as defined herein, wherein the nucleic acid comprises a nucleic acid sequence, which is at least 60%, at least 65%, at least 70%, at least 75%, at least 80%, at least 85%, at least 90%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, at least 99.5%, or 100% identical to the nucleic acid sequence encoding the amino acid sequence as depicted in at least any one of SEQ ID NOs: 1-10, and/or identical to the nucleic acid sequence encoding the amino acid sequence as depicted in at least any one of SEQ ID NOs: 11-23, and/or identical to the nucleic acid sequence encoding the amino acid sequence as depicted in at least any one of SEQ ID NOs: 24-44, preferably as depicted in SEQ ID NOs: 1 , 11 , and 24, even more preferably as depicted in SEQ ID NOs: 1 , 11 , 12, 24 and 25.

[0053] The term “signature sequence or its complementary sequence hereto” may also refer to a nucleic acid as defined elsewhere herein and is called signature sequence due to the fact that it refers to the particular hook the Serratia marcescens phages, the Klebsiella pneumoniae phages, and the Pseudomonas aeruginosa phages within the composition of the invention hybridize to and which can thus be used for targeted Serratia marcescens, Klebsiella pneumoniae, and Pseudomonas aeruginosa phage isolation. In such isolation such hook may act as a primer within qPCR. Such hook (signature sequence or its complementary sequence hereto) is further defined as a nucleic acid comprising a nucleic acid sequence as defined herein encoding an amino acid sequence as depicted in at least any one selected from the group consisting of SEQ ID NOs: 1- 10, and/or a nucleic acid comprising a nucleic acid sequence as defined herein encoding an amino acid sequence as depicted in at least any one selected from the group consisting of SEQ ID NOs: 11-23, and/or a nucleic acid comprising a nucleic acid sequence as defined herein encoding an amino acid sequence as depicted in at least any one selected from the group consisting of SEQ ID NOs: 24-44. “Complementary” means in this context that the complementary sequence to the signature sequence has the base on each position in the complementary (i.e. A to T, C to G) and in the reverse order as the signature sequence as defined above.

[0054] Each signature sequence or its complementary sequence hereto as defined herein encoding an amino acid sequence as depicted in any one selected from the group consisting of SEQ ID NOs: 1-10 refers to a different “hook” which was designed for different first phages after metagenomic sequencing and is used for targeted Serratia marcescens phage isolation. Each signature sequence or its complementary sequence hereto as defined herein encoding an amino acid sequence as depicted in any one selected from the group consisting of SEQ ID NOs: 11-23 refers to a different “hook” which was designed for different second phages after metagenomic sequencing and is used for targeted Klebsiella pneumoniae phage isolation. Each signature sequence or its complementary sequence hereto as defined herein encoding an amino acid sequence as depicted in any one selected from the group consisting of SEQ ID NOs: 24-44 refers to a different “hook” which was designed for different third phages after metagenomic sequencing and is used for targeted Pseudomonas aeruginosa phage isolation. For example, if the first hook refers to the signature sequence encoding SEQ ID NO: 1 (which refers to a major head protein), the second hook refers to the signature sequence encoding SEQ ID NO: 11 (which refers also to a major head protein), and the third hook refers to the signature sequence encoding SEQ ID NO: 24 (which refers also to a major head protein), the composition of the invention may comprise isolated phages which hybridize to such particular hooks, namely isolated phages (“isolated first phages”) that hybridize to SEQ ID NO: 1 , isolated phages (“isolated second phages”) that hybridize to SEQ ID NO: 11 ; and isolated phages (“isolated third phages”) that hybridize to SEQ ID NO: 24. The same applies to the other hooks as defined herein (see at least any one of SEQ ID NOs: 2-10, at least any one of SEQ ID NOs: 12-23, and/or at least any one of SEQ ID NOs: 25-44). Which different Serratia marcescens phages, which different Klebsiella pneumoniae phages, and which different Pseudomonas aeruginosa phages may thus be comprised by the composition of the invention (meaning which Serratia marcescens, Klebsiella pneumoniae, and Pseudomonas aeruginosa phages may be isolated and then comprised by the composition of the invention), is defined by which hook is applied to which the phages hybridize to - however each phage which hybridizes to the hook of at least any one of SEQ ID NOs: 1-10 (‘first phages’) comprised by the composition is capable of infecting bacterial cells (bacteria) Serratia marcescens, and each phage which hybridizes to the hook of at least any one of SEQ ID NOs: 11-23 (‘second phages’) comprised by the composition is capable of infecting bacterial cells (bacteria) Klebsiella pneumoniae, and each phage which hybridizes to the hook of at least any one of SEQ ID NOs: 24-44 (‘third phages’) comprised by the composition is capable of infecting bacterial cells (bacteria) Pseudomonas aeruginosa. This enables a novel composition comprising divergent phages capable of infecting Serratia marcescens which can be isolated by at least any one of the defined hooks (at least any one of SEQ ID NOs: 1-10), and divergent phages capable of infecting Klebsiella pneumoniae which can be isolated by at least any one of the defined hooks (at least any one of SEQ ID NOs: 11-23), and divergent phages capable of infecting Pseudomonas aeruginosa which can be isolated by at least any one of the defined hooks (at least any one SEQ ID NOs: 24-44). As explained elsewhere herein, the hook which encodes the major head protein as defined by SEQ ID NO: 1 is the most abundant protein family within the isolated Serratia marcescens phages after having analysed the genome of the Serratia marcescens phages as defined elsewhere herein. Using such designed hook for targeted phage isolation, targets most Serratia marcescens phages, resulting in the most divergent Serratia marcescens phages for the composition of the invention. The hook which encodes the major head protein as defined by SEQ ID NO: 11 is the most abundant protein family within the isolated Klebsiella pneumoniae phages after having analysed the genome of the Klebsiella pneumoniae phages as defined elsewhere herein. Using such designed hook for targeted phage isolation, targets most Klebsiella pneumoniae phages, resulting in the most divergent Klebsiella pneumoniae phages for the composition of the invention. The hook which encodes the major head protein as defined by SEQ ID NO: 24 is the most abundant protein family within the isolated Pseudomonas aeruginosa phages after having analysed the genome of the Pseudomonas aeruginosa phages as defined elsewhere herein. Using such designed hook for targeted phage isolation, targets most Pseudomonas aeruginosa phages, resulting in the most divergent Pseudomonas aeruginosa phages for the composition of the invention.

[0055] In general, infecting bacteria, such as Serratia marcescens, Klebsiella pneumoniae and Pseudomonas aeruginosa by phages means that such phages either break open (lyses) the bacterial cells immediately by using e.g. polysaccharide-degrading enzymes which enzymatically degrade the capsular outer layer of such bacteria and thus destroys such bacteria after immediate replication within said bacteria (if it is a lytic phage) or do not lyse the host cells, such as bacteria cells Serratia marcescens, Klebsiella pneumoniae and Pseudomonas aeruginosa, immediately, but its viral genome integrates with host DNA and replicates along with it before then initiating the reproductive cycle, resulting in lysis of the host cell (if it is a lysogenic phage). In the context of the invention, the phages infecting Serratia marcescens, Klebsiella pneumoniae and Pseudomonas aeruginosa and which hybridize to the defined hook(s) may refer to lytic phages. To inject a host cell, such as Serratia marcescens, Klebsiella pneumoniae and Pseudomonas aeruginosa, the phages bind to specific receptors on the surface of Serratia marcescens, Klebsiella pneumoniae and Pseudomonas aeruginosa such as, but not limited to, outer membrane proteins, polysaccharides, lipopolysaccharides (LPS) and carbohydrate moieties. Thereby, the phages specifically infect only those bacteria, in the case of the invention Serratia marcescens, Klebsiella pneumoniae and Pseudomonas aeruginosa, bearing certain receptors on their surface to which the phages bind to.

[0056] The Serratia marcescens phages which refer to the “first phages” within the composition of the invention as used throughout the application which can be isolated by at least any one of the hooks as depicted by SEQ ID NOs: 1-10 are capable of suppressing the growth of Serratia marcescens bacterial cells such that OD600 is not higher than 0.5. Meaning, such phages are capable of infecting Serratia marcescens as outlined elsewhere herein and thus the growth of such bacterial cells is suppressed in comparison to the growth of such bacterial cells if the cells were not infected by such phages (see Figure 2). The same applies mutatis mutandis to such Klebsiella pneumoniae phages which refer to the “second phages” within the composition of the invention as used throughout the application which can be isolated by at least any one of the hooks as depicted by SEQ ID NOs: 11-23 (see Figure 3) and to such Pseudomonas aeruginosa phages which refer to the “third phages” within the composition of the invention as used throughout the application which can be isolated by at least any one of the hooks as depicted by SEQ ID NOs: 24-44 (see Figure 4). Within the composition of the invention where Serratia marcescens, Klebsiella pneumoniae, and Pseudomonas aeruginosa phages are all combined, the composition comprising such isolated first, second and third phages as defined herein is also capable of infecting Serratia marcescens, Klebsiella pneumoniae and Pseudomonas aeruginosa phages. Thereby, such composition comprising such isolated first, second and third phages as defined herein is capable of suppressing the growth of Serratia marcescens, Klebsiella pneumoniae and Pseudomonas aeruginosa phages such that OD600 is not higher than 0.5 or below 0.5 (for at least 10, 15, 20, 30, 40 or 45 hours) (see Figure 6). Such effect can also be seen in vivo, where the survival rate of the larvae model is increased after having applied the phage cocktail as defined herein compared to the control larvae being treated with just the bacteria and without the phage cocktail (see Figure 7).

[0057] With using QD600 as a turbidity measurement known to the skilled person which refers to the optical density of a sample measured at a wavelength of 600 nm in 1 cm light path the concentration of bacterial cells, such as of Serratia marcescens, Klebsiella pneumoniae, and Pseudomonas aeruginosa, in a liquid can be estimated as the wavelength of 600 nm does not hinder the growth of such bacterial cells. The growth of such bacterial cells can be controlled by measuring the optical density at 600 nm (QD600). QD600 measurements can typically be used to determine the stage of growth of such bacterial cells. Growth of bacterial cells typically progresses through a series of consecutive phases including lag, log, stationary, and decline as known to a person skilled. Changes of the QD600 as a function of time (i.e. as measuring the growth curve) thus indicates the growth phase of such bacterial cells. As can be seen from Figures 2- 4 as outlined above such QD600 is below 0.5 or not higher than 0.5 (for at least 12, 15, 20 or 24 hours) meaning that the growth of Serratia marcescens, Klebsiella pneumoniae, and Pseudomonas aeruginosa bacteria is inhibited if the corresponding phages are applied to the bacterial culture to infect such bacteria in comparison to the growth of such bacteria if such phages were not applied to the culture, thereby not inhibiting the growth of the bacterial cells.

[0058] In a preferred embodiment, the present invention comprises the composition as defined herein, wherein i) said first phages as described herein are capable of suppressing growth of Serratia marcescens such that OD600 is below or not higher than 0.2 (for at least 12, 15, 20 or 24 hours); ii) said second phages as described herein are capable of suppressing growth of Klebsiella pneumoniae such that OD600 is below or not higher than 0.2 (for at least 12, 15, 20 or 24 hours), and iii) said third phages as defined herein are capable of suppressing growth of Pseudomonas aeruginosa such that OD600 is below or not higher than 0.2 (for at least 12, 15, 20 or 24 hours). Such composition comprising such isolated first, second and third phages as defined herein is thus capable of suppressing the growth of Serratia marcescens, Klebsiella pneumoniae and Pseudomonas aeruginosa such that OD600 is below or not higher than 0.2 (for at least 10, 15, 20, 30, 40 or 45 hours) (see Figure 6).

[0059] The present invention may thus comprise the composition as defined herein, wherein said composition has bactericidal activity against at least any one of Serratia marcescens, Klebsiella pneumoniae or Pseudomonas aeruginosa, preferably said composition has bactericidal activity against Serratia marcescens, Klebsiella pneumoniae and Pseudomonas aeruginosa. Meaning by applying such composition, e.g. comprised within a pharmaceutical composition, such composition comprising the particular phages is able to take action against the bacterial cell Serratia marcescens, Klebsiella pneumoniae and/or Pseudomonas aeruginosa by infecting said bacteria as defined herein, thereby preventing the development of bacterial cell resistance and thus resulting in an efficient bacterial removal of Serratia marcescens, Klebsiella pneumoniae and/or Pseudomonas aeruginosa.

[0060] Such Serratia marcescens, Klebsiella pneumoniae and Pseudomonas aeruginosa can refer to an antimicrobial resistance (AMR) bacterial cell. In this context, as used herein unless specified otherwise, “antimicrobial resistance” may be used interchangeably with “drug resistance” and comprises resistance to at least antibiotic agents known in the art, i.e. the ability of a bacterial cell to resist the effects of a drug or agent that could otherwise successfully treat said bacterial cell. Serratia marcescens, Klebsiella pneumoniae and Pseudomonas aeruginosa may acquire AMR genes mediating resistance mostly to aminoglycosides, cephalosporins, carbapenems, sulfonamides, tetracyclines and macrolides (Wareth et al. 202, BMC Micobiol 10;21 (1 ):210). The term “antimicrobial resistance” as used herein thus also comprises the term “antibiotic resistance” as known in the art. The present invention may therefore also envisage the composition as defined herein, wherein the Serratia marcescens, Klebsiella pneumoniae and Pseudomonas aeruginosa bacteria are AMR bacteria. The inventors found out that the composition as defined herein comprising said isolated first, second and third phages have been shown to resensitize such AMR bacteria to antibiotics, potentially enhancing the efficacy of conventional antimicrobial treatments resulting in a synergistic effect. It was shown that the phage composition as defined herein comprising the isolated first, second and third phages, preferably the particular phage cocktail as defined elsewhere herein, can weaken bacterial defenses, for example, making them more susceptible to antibiotics such as Meropenem (see Figure 8A and B). Thus, the present invention also comprises the composition or the pharmaceutical composition as defined elsewhere herein, which is administered in combination with an antibiotic, such as a carbapenem, preferably Meropenem.

[0061] In an embodiment of the present invention, the invention comprises a composition comprising: a) isolated first phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in at least any one of SEQ ID NOs: 1-10, wherein the phages are capable of suppressing growth of Serratia marcescens such that OD600 is not higher than 0.5; b) isolated second phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 11 , wherein the phages are capable of suppressing growth of Klebsiella pneumoniae such that QD600 is not higher than 0.5; and c) isolated third phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 24, wherein the phages are capable of suppressing growth of Pseudomonas aeruginosa such that QD600 is not higher than 0.5.

[0062] In an embodiment of the present invention, the invention comprises a composition comprising: a) isolated first phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 1 , wherein the phages are capable of suppressing growth of Serratia marcescens such that QD600 is not higher than 0.5; b) isolated second phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in at least any one of SEQ ID NOs: 11-23, wherein the phages are capable of suppressing growth of Klebsiella pneumoniae such that QD600 is not higher than 0.5; and c) isolated third phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 24, wherein the phages are capable of suppressing growth of Pseudomonas aeruginosa such that OD600 is not higher than 0.5. In a further embodiment, the invention comprises a composition comprising: a) isolated first phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 1 , wherein the phages are capable of suppressing growth of Serratia marcescens such that OD600 is not higher than 0.5; b) isolated second phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 12, wherein the phages are capable of suppressing growth of Klebsiella pneumoniae such that OD600 is not higher than 0.5; and c) isolated third phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 24, wherein the phages are capable of suppressing growth of Pseudomonas aeruginosa such that OD600 is not higher than 0.5. In a further embodiment, the invention comprises a composition comprising: a) isolated first phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 1 , wherein the phages are capable of suppressing growth of Serratia marcescens such that OD600 is not higher than 0.5; b) isolated second phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 13, wherein the phages are capable of suppressing growth of Klebsiella pneumoniae such that OD600 is not higher than 0.5; and c) isolated third phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 24, wherein the phages are capable of suppressing growth of Pseudomonas aeruginosa such that OD600 is not higher than 0.5. In a further embodiment, the invention comprises a composition comprising: a) isolated first phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 1 , wherein the phages are capable of suppressing growth of Serratia marcescens such that OD600 is not higher than 0.5; b) isolated second phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 14, wherein the phages are capable of suppressing growth of Klebsiella pneumoniae such that OD600 is not higher than 0.5; and c) isolated third phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 24, wherein the phages are capable of suppressing growth of Pseudomonas aeruginosa such that QD600 is not higher than 0.5. In a further embodiment, the invention comprises a composition comprising: a) isolated first phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 1 , wherein the phages are capable of suppressing growth of Serratia marcescens such that QD600 is not higher than 0.5; b) isolated second phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 15, wherein the phages are capable of suppressing growth of Klebsiella pneumoniae such that QD600 is not higher than 0.5; and c) isolated third phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 24, wherein the phages are capable of suppressing growth of Pseudomonas aeruginosa such that QD600 is not higher than 0.5. In a further embodiment, the invention comprises a composition comprising: a) isolated first phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 1 , wherein the phages are capable of suppressing growth of Serratia marcescens such that QD600 is not higher than 0.5; b) isolated second phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 16, wherein the phages are capable of suppressing growth of Klebsiella pneumoniae such that QD600 is not higher than 0.5; and c) isolated third phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 24, wherein the phages are capable of suppressing growth of Pseudomonas aeruginosa such that QD600 is not higher than 0.5. In a further embodiment, the invention comprises a composition comprising: a) isolated first phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 1 , wherein the phages are capable of suppressing growth of Serratia marcescens such that OD600 is not higher than 0.5; b) isolated second phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 17, wherein the phages are capable of suppressing growth of Klebsiella pneumoniae such that OD600 is not higher than 0.5; and c) isolated third phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 24, wherein the phages are capable of suppressing growth of Pseudomonas aeruginosa such that QD600 is not higher than 0.5. In a further embodiment, the invention comprises a composition comprising: a) isolated first phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 1 , wherein the phages are capable of suppressing growth of Serratia marcescens such that QD600 is not higher than 0.5; b) isolated second phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 18, wherein the phages are capable of suppressing growth of Klebsiella pneumoniae such that QD600 is not higher than 0.5; and c) isolated third phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 24, wherein the phages are capable of suppressing growth of Pseudomonas aeruginosa such that QD600 is not higher than 0.5. In a further embodiment, the invention comprises a composition comprising: a) isolated first phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 1 , wherein the phages are capable of suppressing growth of Serratia marcescens such that QD600 is not higher than 0.5; b) isolated second phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 19, wherein the phages are capable of suppressing growth of Klebsiella pneumoniae such that QD600 is not higher than 0.5; and c) isolated third phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 24, wherein the phages are capable of suppressing growth of Pseudomonas aeruginosa such that QD600 is not higher than 0.5. In a further embodiment, the invention comprises a composition comprising: a) isolated first phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 1 , wherein the phages are capable of suppressing growth of Serratia marcescens such that OD600 is not higher than 0.5; b) isolated second phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 20, wherein the phages are capable of suppressing growth of Klebsiella pneumoniae such that QD600 is not higher than 0.5; and c) isolated third phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 24, wherein the phages are capable of suppressing growth of Pseudomonas aeruginosa such that QD600 is not higher than 0.5. In a further embodiment, the invention comprises a composition comprising: a) isolated first phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 1 , wherein the phages are capable of suppressing growth of Serratia marcescens such that QD600 is not higher than 0.5; b) isolated second phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 21 , wherein the phages are capable of suppressing growth of Klebsiella pneumoniae such that QD600 is not higher than 0.5; and c) isolated third phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 24, wherein the phages are capable of suppressing growth of Pseudomonas aeruginosa such that QD600 is not higher than 0.5. In a further embodiment, the invention comprises a composition comprising: a) isolated first phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 1 , wherein the phages are capable of suppressing growth of Serratia marcescens such that QD600 is not higher than 0.5; b) isolated second phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 22, wherein the phages are capable of suppressing growth of Klebsiella pneumoniae such that QD600 is not higher than 0.5; and c) isolated third phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 24, wherein the phages are capable of suppressing growth of Pseudomonas aeruginosa such that OD600 is not higher than 0.5. In a further embodiment, the invention comprises a composition comprising: a) isolated first phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 1 , wherein the phages are capable of suppressing growth of Serratia marcescens such that OD600 is not higher than 0.5; b) isolated second phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 23, wherein the phages are capable of suppressing growth of Klebsiella pneumoniae such that QD600 is not higher than 0.5; and c) isolated third phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 24, wherein the phages are capable of suppressing growth of Pseudomonas aeruginosa such that QD600 is not higher than 0.5.

[0063] In a further embodiment, the invention comprises a composition comprising: a) isolated first phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 2, wherein the phages are capable of suppressing growth of Serratia marcescens such that QD600 is not higher than 0.5; b) isolated second phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in at least any one of SEQ ID NOs: 11-23, wherein the phages are capable of suppressing growth of Klebsiella pneumoniae such that QD600 is not higher than 0.5; and c) isolated third phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 24, wherein the phages are capable of suppressing growth of Pseudomonas aeruginosa such that QD600 is not higher than 0.5. In a further embodiment, the invention comprises a composition comprising: a) isolated first phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 2, wherein the phages are capable of suppressing growth of Serratia marcescens such that QD600 is not higher than 0.5; b) isolated second phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 11, wherein the phages are capable of suppressing growth of Klebsiella pneumoniae such that OD600 is not higher than 0.5; and c) isolated third phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 24, wherein the phages are capable of suppressing growth of Pseudomonas aeruginosa such that OD600 is not higher than 0.5. In a further embodiment, the invention comprises a composition comprising: a) isolated first phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 2, wherein the phages are capable of suppressing growth of Serratia marcescens such that OD600 is not higher than 0.5; b) isolated second phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 12, wherein the phages are capable of suppressing growth of Klebsiella pneumoniae such that OD600 is not higher than 0.5; and c) isolated third phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 24, wherein the phages are capable of suppressing growth of Pseudomonas aeruginosa such that OD600 is not higher than 0.5. In a further embodiment, the invention comprises a composition comprising: a) isolated first phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 2, wherein the phages are capable of suppressing growth of Serratia marcescens such that OD600 is not higher than 0.5; b) isolated second phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 13, wherein the phages are capable of suppressing growth of Klebsiella pneumoniae such that OD600 is not higher than 0.5; and c) isolated third phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 24, wherein the phages are capable of suppressing growth of Pseudomonas aeruginosa such that OD600 is not higher than 0.5. In a further embodiment, the invention comprises a composition comprising: a) isolated first phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 2, wherein the phages are capable of suppressing growth of Serratia marcescens such that OD600 is not higher than 0.5; b) isolated second phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 14, wherein the phages are capable of suppressing growth of Klebsiella pneumoniae such that OD600 is not higher than 0.5; and c) isolated third phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 24, wherein the phages are capable of suppressing growth of Pseudomonas aeruginosa such that QD600 is not higher than 0.5. In a further embodiment, the invention comprises a composition comprising: a) isolated first phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 2, wherein the phages are capable of suppressing growth of Serratia marcescens such that QD600 is not higher than 0.5; b) isolated second phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 15, wherein the phages are capable of suppressing growth of Klebsiella pneumoniae such that QD600 is not higher than 0.5; and c) isolated third phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 24, wherein the phages are capable of suppressing growth of Pseudomonas aeruginosa such that QD600 is not higher than 0.5. In a further embodiment, the invention comprises a composition comprising: a) isolated first phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 2, wherein the phages are capable of suppressing growth of Serratia marcescens such that QD600 is not higher than 0.5; b) isolated second phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 16, wherein the phages are capable of suppressing growth of Klebsiella pneumoniae such that QD600 is not higher than 0.5; and c) isolated third phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 24, wherein the phages are capable of suppressing growth of Pseudomonas aeruginosa such that QD600 is not higher than 0.5. In a further embodiment, the invention comprises a composition comprising: a) isolated first phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 2, wherein the phages are capable of suppressing growth of Serratia marcescens such that OD600 is not higher than 0.5; b) isolated second phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 17, wherein the phages are capable of suppressing growth of Klebsiella pneumoniae such that QD600 is not higher than 0.5; and c) isolated third phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 24, wherein the phages are capable of suppressing growth of Pseudomonas aeruginosa such that QD600 is not higher than 0.5. In a further embodiment, the invention comprises a composition comprising: a) isolated first phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 2, wherein the phages are capable of suppressing growth of Serratia marcescens such that QD600 is not higher than 0.5; b) isolated second phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 8, wherein the phages are capable of suppressing growth of Klebsiella pneumoniae such that OD600 is not higher than 0.5; and c) isolated third phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 24, wherein the phages are capable of suppressing growth of Pseudomonas aeruginosa such that OD600 is not higher than 0.5. In a further embodiment, the invention comprises a composition comprising: a) isolated first phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 2, wherein the phages are capable of suppressing growth of Serratia marcescens such that OD600 is not higher than 0.5; b) isolated second phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 19, wherein the phages are capable of suppressing growth of Klebsiella pneumoniae such that OD600 is not higher than 0.5; and c) isolated third phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 24, wherein the phages are capable of suppressing growth of Pseudomonas aeruginosa such that OD600 is not higher than 0.5. In a further embodiment, the invention comprises a composition comprising: a) isolated first phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 2, wherein the phages are capable of suppressing growth of Serratia marcescens such that OD600 is not higher than 0.5; b) isolated second phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 20, wherein the phages are capable of suppressing growth of Klebsiella pneumoniae such that QD600 is not higher than 0.5; and c) isolated third phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 24, wherein the phages are capable of suppressing growth of Pseudomonas aeruginosa such that QD600 is not higher than 0.5. In a further embodiment, the invention comprises a composition comprising: a) isolated first phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 2, wherein the phages are capable of suppressing growth of Serratia marcescens such that QD600 is not higher than 0.5; b) isolated second phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 21 , wherein the phages are capable of suppressing growth of Klebsiella pneumoniae such that QD600 is not higher than 0.5; and c) isolated third phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 24, wherein the phages are capable of suppressing growth of Pseudomonas aeruginosa such that OD600 is not higher than 0.5. In a further embodiment, the invention comprises a composition comprising: a) isolated first phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 2, wherein the phages are capable of suppressing growth of Serratia marcescens such that OD600 is not higher than 0.5; b) isolated second phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 22, wherein the phages are capable of suppressing growth of Klebsiella pneumoniae such that OD600 is not higher than 0.5; and c) isolated third phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 24, wherein the phages are capable of suppressing growth of Pseudomonas aeruginosa such that OD600 is not higher than 0.5. In a further embodiment, the invention comprises a composition comprising: a) isolated first phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 2, wherein the phages are capable of suppressing growth of Serratia marcescens such that QD600 is not higher than 0.5; b) isolated second phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 23, wherein the phages are capable of suppressing growth of Klebsiella pneumoniae such that QD600 is not higher than 0.5; and c) isolated third phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 24, wherein the phages are capable of suppressing growth of Pseudomonas aeruginosa such that QD600 is not higher than 0.5.

[0064] In a further embodiment, the invention comprises a composition comprising: a) isolated first phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 1 , wherein the phages are capable of suppressing growth of Serratia marcescens such that QD600 is not higher than 0.5; b) isolated second phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 11 , wherein the phages are capable of suppressing growth of Klebsiella pneumoniae such that QD600 is not higher than 0.5; and c) isolated third phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in at least any one of SEQ ID NOs: 24-44, wherein the phages are capable of suppressing growth of Pseudomonas aeruginosa such that QD600 is not higher than 0.5. In a further embodiment, the invention comprises a composition comprising: a) isolated first phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 1 , wherein the phages are capable of suppressing growth of Serratia marcescens such that QD600 is not higher than 0.5; b) isolated second phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 12, wherein the phages are capable of suppressing growth of Klebsiella pneumoniae such that OD600 is not higher than 0.5; and c) isolated third phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in at least any one of SEQ ID NOs: 24-44, wherein the phages are capable of suppressing growth of Pseudomonas aeruginosa such that QD600 is not higher than 0.5. In a further embodiment, the invention comprises a composition comprising: a) isolated first phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 1 , wherein the phages are capable of suppressing growth of Serratia marcescens such that QD600 is not higher than 0.5; b) isolated second phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 13, wherein the phages are capable of suppressing growth of Klebsiella pneumoniae such that QD600 is not higher than 0.5; and c) isolated third phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in at least any one of SEQ ID NOs: 24-44, wherein the phages are capable of suppressing growth of Pseudomonas aeruginosa such that QD600 is not higher than 0.5. In a further embodiment, the invention comprises a composition comprising: a) isolated first phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 1 , wherein the phages are capable of suppressing growth of Serratia marcescens such that QD600 is not higher than 0.5; b) isolated second phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 14, wherein the phages are capable of suppressing growth of Klebsiella pneumoniae such that QD600 is not higher than 0.5; and c) isolated third phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in at least any one of SEQ ID NOs: 24-44, wherein the phages are capable of suppressing growth of Pseudomonas aeruginosa such that QD600 is not higher than 0.5. In a further embodiment, the invention comprises a composition comprising: a) isolated first phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 1 , wherein the phages are capable of suppressing growth of Serratia marcescens such that OD600 is not higher than 0.5; b) isolated second phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 15, wherein the phages are capable of suppressing growth of Klebsiella pneumoniae such that OD600 is not higher than 0.5; and c) isolated third phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in at least any one of SEQ ID NOs: 24-44, wherein the phages are capable of suppressing growth of Pseudomonas aeruginosa such that QD600 is not higher than 0.5. In a further embodiment, the invention comprises a composition comprising: a) isolated first phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 1 , wherein the phages are capable of suppressing growth of Serratia marcescens such that QD600 is not higher than 0.5; b) isolated second phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 16, wherein the phages are capable of suppressing growth of Klebsiella pneumoniae such that QD600 is not higher than 0.5; and c) isolated third phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in at least any one of SEQ ID NOs: 24-44, wherein the phages are capable of suppressing growth of Pseudomonas aeruginosa such that QD600 is not higher than 0.5. In a further embodiment, the invention comprises a composition comprising: a) isolated first phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 1 , wherein the phages are capable of suppressing growth of Serratia marcescens such that QD600 is not higher than 0.5; b) isolated second phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 17, wherein the phages are capable of suppressing growth of Klebsiella pneumoniae such that QD600 is not higher than 0.5; and c) isolated third phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in at least any one of SEQ ID NOs: 24-44, wherein the phages are capable of suppressing growth of Pseudomonas aeruginosa such that QD600 is not higher than 0.5. In a further embodiment, the invention comprises a composition comprising: a) isolated first phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 1 , wherein the phages are capable of suppressing growth of Serratia marcescens such that OD600 is not higher than 0.5; b) isolated second phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 18, wherein the phages are capable of suppressing growth of Klebsiella pneumoniae such that QD600 is not higher than 0.5; and c) isolated third phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in at least any one of SEQ ID NOs: 24-44, wherein the phages are capable of suppressing growth of Pseudomonas aeruginosa such that QD600 is not higher than 0.5. In a further embodiment, the invention comprises a composition comprising: a) isolated first phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 1 , wherein the phages are capable of suppressing growth of Serratia marcescens such that QD600 is not higher than 0.5; b) isolated second phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 19, wherein the phages are capable of suppressing growth of Klebsiella pneumoniae such that QD600 is not higher than 0.5; and c) isolated third phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in at least any one of SEQ ID NOs: 24-44, wherein the phages are capable of suppressing growth of Pseudomonas aeruginosa such that QD600 is not higher than 0.5. In a further embodiment, the invention comprises a composition comprising: a) isolated first phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 1 , wherein the phages are capable of suppressing growth of Serratia marcescens such that QD600 is not higher than 0.5; b) isolated second phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 20, wherein the phages are capable of suppressing growth of Klebsiella pneumoniae such that QD600 is not higher than 0.5; and c) isolated third phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in at least any one of SEQ ID NOs: 24-44, wherein the phages are capable of suppressing growth of Pseudomonas aeruginosa such that OD600 is not higher than 0.5. In a further embodiment, the invention comprises a composition comprising: a) isolated first phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 1 , wherein the phages are capable of suppressing growth of Serratia marcescens such that QD600 is not higher than 0.5; b) isolated second phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 21 , wherein the phages are capable of suppressing growth of Klebsiella pneumoniae such that QD600 is not higher than 0.5; and c) isolated third phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in at least any one of SEQ ID NOs: 24-44, wherein the phages are capable of suppressing growth of Pseudomonas aeruginosa such that QD600 is not higher than 0.5. In a further embodiment, the invention comprises a composition comprising: a) isolated first phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 1 , wherein the phages are capable of suppressing growth of Serratia marcescens such that QD600 is not higher than 0.5; b) isolated second phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 22, wherein the phages are capable of suppressing growth of Klebsiella pneumoniae such that QD600 is not higher than 0.5; and c) isolated third phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in at least any one of SEQ ID NOs: 24-44, wherein the phages are capable of suppressing growth of Pseudomonas aeruginosa such that QD600 is not higher than 0.5. In a further embodiment, the invention comprises a composition comprising: a) isolated first phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 1 , wherein the phages are capable of suppressing growth of Serratia marcescens such that QD600 is not higher than 0.5; b) isolated second phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 23, wherein the phages are capable of suppressing growth of Klebsiella pneumoniae such that OD600 is not higher than 0.5; and c) isolated third phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in at least any one of SEQ ID NOs: 24-44, wherein the phages are capable of suppressing growth of Pseudomonas aeruginosa such that QD600 is not higher than 0.5.

[0065] In a further embodiment, the invention comprises a composition comprising: a) isolated first phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 2, wherein the phages are capable of suppressing growth of Serratia marcescens such that QD600 is not higher than 0.5; b) isolated second phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 11 , wherein the phages are capable of suppressing growth of Klebsiella pneumoniae such that QD600 is not higher than 0.5; and c) isolated third phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in at least any one of SEQ ID NOs: 24-44, wherein the phages are capable of suppressing growth of Pseudomonas aeruginosa such that QD600 is not higher than 0.5. In a further embodiment, the invention comprises a composition comprising: a) isolated first phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 2, wherein the phages are capable of suppressing growth of Serratia marcescens such that QD600 is not higher than 0.5; b) isolated second phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 12, wherein the phages are capable of suppressing growth of Klebsiella pneumoniae such that QD600 is not higher than 0.5; and c) isolated third phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in at least any one of SEQ ID NOs: 24-44, wherein the phages are capable of suppressing growth of Pseudomonas aeruginosa such that QD600 is not higher than 0.5. In a further embodiment, the invention comprises a composition comprising: a) isolated first phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 2, wherein the phages are capable of suppressing growth of Serratia marcescens such that OD600 is not higher than 0.5; b) isolated second phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 13, wherein the phages are capable of suppressing growth of Klebsiella pneumoniae such that QD600 is not higher than 0.5; and c) isolated third phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in at least any one of SEQ ID NOs: 24-44, wherein the phages are capable of suppressing growth of Pseudomonas aeruginosa such that QD600 is not higher than 0.5. In a further embodiment, the invention comprises a composition comprising: a) isolated first phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 2, wherein the phages are capable of suppressing growth of Serratia marcescens such that QD600 is not higher than 0.5; b) isolated second phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 14, wherein the phages are capable of suppressing growth of Klebsiella pneumoniae such that QD600 is not higher than 0.5; and c) isolated third phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in at least any one of SEQ ID NOs: 24-44, wherein the phages are capable of suppressing growth of Pseudomonas aeruginosa such that QD600 is not higher than 0.5. In a further embodiment, the invention comprises a composition comprising: a) isolated first phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 2, wherein the phages are capable of suppressing growth of Serratia marcescens such that QD600 is not higher than 0.5; b) isolated second phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 15, wherein the phages are capable of suppressing growth of Klebsiella pneumoniae such that QD600 is not higher than 0.5; and c) isolated third phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in at least any one of SEQ ID NOs: 24-44, wherein the phages are capable of suppressing growth of Pseudomonas aeruginosa such that QD600 is not higher than 0.5. In a further embodiment, the invention comprises a composition comprising: a) isolated first phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 2, wherein the phages are capable of suppressing growth of Serratia marcescens such that OD600 is not higher than 0.5; b) isolated second phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 16, wherein the phages are capable of suppressing growth of Klebsiella pneumoniae such that OD600 is not higher than 0.5; and c) isolated third phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in at least any one of SEQ ID NOs: 24-44, wherein the phages are capable of suppressing growth of Pseudomonas aeruginosa such that QD600 is not higher than 0.5. In a further embodiment, the invention comprises a composition comprising: a) isolated first phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 2, wherein the phages are capable of suppressing growth of Serratia marcescens such that QD600 is not higher than 0.5; b) isolated second phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 17, wherein the phages are capable of suppressing growth of Klebsiella pneumoniae such that OD600 is not higher than 0.5; and c) isolated third phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in at least any one of SEQ ID NOs: 24-44, wherein the phages are capable of suppressing growth of Pseudomonas aeruginosa such that OD600 is not higher than 0.5. In a further embodiment, the invention comprises a composition comprising: a) isolated first phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 2, wherein the phages are capable of suppressing growth of Serratia marcescens such that OD600 is not higher than 0.5; b) isolated second phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 18, wherein the phages are capable of suppressing growth of Klebsiella pneumoniae such that OD600 is not higher than 0.5; and c) isolated third phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in at least any one of SEQ ID NOs: 24-44, wherein the phages are capable of suppressing growth of Pseudomonas aeruginosa such that OD600 is not higher than 0.5. In a further embodiment, the invention comprises a composition comprising: a) isolated first phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 2, wherein the phages are capable of suppressing growth of Serratia marcescens such that QD600 is not higher than 0.5; b) isolated second phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 19, wherein the phages are capable of suppressing growth of Klebsiella pneumoniae such that QD600 is not higher than 0.5; and c) isolated third phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in at least any one of SEQ ID NOs: 24-44, wherein the phages are capable of suppressing growth of Pseudomonas aeruginosa such that QD600 is not higher than 0.5. In a further embodiment, the invention comprises a composition comprising: a) isolated first phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 2, wherein the phages are capable of suppressing growth of Serratia marcescens such that QD600 is not higher than 0.5; b) isolated second phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 20, wherein the phages are capable of suppressing growth of Klebsiella pneumoniae such that QD600 is not higher than 0.5; and c) isolated third phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in at least any one of SEQ ID NOs: 24-44, wherein the phages are capable of suppressing growth of Pseudomonas aeruginosa such that QD600 is not higher than 0.5. In a further embodiment, the invention comprises a composition comprising: a) isolated first phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 2, wherein the phages are capable of suppressing growth of Serratia marcescens such that QD600 is not higher than 0.5; b) isolated second phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 21 , wherein the phages are capable of suppressing growth of Klebsiella pneumoniae such that OD600 is not higher than 0.5; and c) isolated third phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in at least any one of SEQ ID NOs: 24-44, wherein the phages are capable of suppressing growth of Pseudomonas aeruginosa such that QD600 is not higher than 0.5. In a further embodiment, the invention comprises a composition comprising: a) isolated first phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 2, wherein the phages are capable of suppressing growth of Serratia marcescens such that QD600 is not higher than 0.5; b) isolated second phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 22, wherein the phages are capable of suppressing growth of Klebsiella pneumoniae such that QD600 is not higher than 0.5; and c) isolated third phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in at least any one of SEQ ID NOs: 24-44, wherein the phages are capable of suppressing growth of Pseudomonas aeruginosa such that QD600 is not higher than 0.5. In a further embodiment, the invention comprises a composition comprising: a) isolated first phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 2, wherein the phages are capable of suppressing growth of Serratia marcescens such that QD600 is not higher than 0.5; b) isolated second phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 23, wherein the phages are capable of suppressing growth of Klebsiella pneumoniae such that OD600 is not higher than 0.5; and c) isolated third phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in at least any one of SEQ ID NOs: 24-44, wherein the phages are capable of suppressing growth of Pseudomonas aeruginosa such that OD600 is not higher than 0.5.

[0066] In a most preferred embodiment of the present invention, the invention comprises a composition comprising: a) isolated first phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 1 , wherein the phages are capable of suppressing growth of Serratia marcescens such that OD600 is not higher than 0.5; b) isolated second phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 11 , wherein the phages are capable of suppressing growth of Klebsiella pneumoniae such that QD600 is not higher than 0.5; and c) isolated third phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 24, wherein the phages are capable of suppressing growth of Pseudomonas aeruginosa such that QD600 is not higher than 0.5.

[0067] In another embodiment of the present invention, the invention comprises a composition comprising: a) isolated first phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 1 , wherein the phages are capable of suppressing growth of Serratia marcescens such that QD600 is not higher than 0.5; b) isolated second phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 11 and isolated different second phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 12, wherein the phages are capable of suppressing growth of Klebsiella pneumoniae such that QD600 is not higher than 0.5; and c) isolated third phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in at least any one of SEQ ID NOs: 24-44, wherein the phages are capable of suppressing growth of Pseudomonas aeruginosa such that QD600 is not higher than 0.5.

[0068] In another embodiment of the present invention, the invention comprises a composition comprising: a) isolated first phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 1 , wherein the phages are capable of suppressing growth of Serratia marcescens such that QD600 is not higher than 0.5; b) isolated second phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in at least any one of SEQ ID NOs: 11-23, wherein the phages are capable of suppressing growth of Klebsiella pneumoniae such that GD600 is not higher than 0.5; and c) isolated third phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 24 and isolated different third phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 25, wherein the phages are capable of suppressing growth of Pseudomonas aeruginosa such that QD600 is not higher than 0.5.

[0069] In another embodiment of the present invention, the invention comprises a composition comprising: a) isolated first phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 1 , wherein the phages are capable of suppressing growth of Serratia marcescens such that QD600 is not higher than 0.5; b) isolated second phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 11 and isolated different second phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 12, wherein the phages are capable of suppressing growth of Klebsiella pneumoniae such that QD600 is not higher than 0.5; and c) isolated third phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 24 and isolated different third phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 25, wherein the phages are capable of suppressing growth of Pseudomonas aeruginosa such that QD600 is not higher than 0.5.

[0070] In a most preferred embodiment of the invention, the composition as defined elsewhere herein comprises one or more phages which infect Serratia marcescens selected from the group consisting of HMGUsml , SMC1O0610, and SMC1400610 (see Figure 2), preferably HMGUsml (corresponds to phage SM12G0109A, see Figure 1A), further comprising one or more phages which infect Klebsiella pneumoniae selected from the group consisting of HMGUkpl and HMGUkp2 (see Figure 3), preferably HMGUkpl and HMGUkp2 (correspond to phage KPD, see Figure 1 B), further comprising one or more phages which infect Pseudomonas aeruginosa selected from the group consisting of HMGUpa3 and HMGUpa4 (see Figure 4), preferably HMGUpa3 (corresponds to phage F2, see Figure 1C) and HMGUpa4 (corresponds to phage P10g2, see also Figure 1C). Said particular, novel and unpublished phages have been given a unique name by the inventors of the Helmholz Zentrum Muenchen- Deutsches Forschungszentrum fur Gesundheit und Umwelt (HMGU) which identifies their hosts such as Serratia marcescens (sm), Klebsiella pneumoniae (kp) and Pseudomonas aeruginosa (pa) based on the newly applied regulations for naming phages. Thus, the most preferred composition of the invention is a composition comprising HMGUsml , HMGUkpl , HMGUkp2, HMGUpa3 and HMGUpa4 (see Figure 6, “phage cocktail”). When applying such phage composition comprising all five phages (phage cocktail), the composition is capable of suppressing growth of Serratia marcescens, Klebsiella pneumoniae and Pseudomonas aeruginosa such that GD600 is bellow or not higher than 0.5, preferably below or not higher than 0.2 as defined herein and/or of resensitizing AMR bacteria to antibiotics, potentially enhancing the efficacy of conventional antimicrobial treatments (see Figure 8A and B).

[0071] The Serratia marcescens phage labeled “HMGUsml” binds to five signature sequences (or complementary sequences hereto) each comprising a nucleic acid sequence, wherein the first one encodes an amino acid sequence as depicted in SEQ ID NO: 1 , the second one encodes an amino acid sequence as depicted in SEQ ID NO: 2, the third one encodes an amino acid sequence as depicted in SEQ ID NO: 8, the fourth one encodes an amino acid sequence as depicted in SEQ ID NO: 9, the fifth one encodes an amino acid sequence as depicted in SEQ ID NO: 10, the signature sequence (or complementary sequence hereto) encoding an amino acid sequence as depicted in SEQ ID NO: 1 as the hook with regard to all 10 hooks depicted herein (see SEQ ID NOs: 1-10) where the most Serratia marcescens phages hybridize to - among others HMGUsml . The Klebsiella pneumoniae phage labeled “HMGUkpl” binds to other five signature sequences (or complementary sequences hereto) each comprising a nucleic acid sequence, wherein the first one encodes an amino acid sequence as depicted in SEQ ID NO: 11 , the second one encodes an amino acid sequence as depicted in SEQ ID NO: 13, the third one encodes an amino acid sequence as depicted in SEQ ID NO: 14, the fourth one encodes an amino acid sequence as depicted in SEQ ID NO: 16, the fifth one encodes an amino acid sequence as depicted in SEQ ID NO: 23, the signature sequence (or complementary sequence hereto) encoding an amino acid sequence as depicted in SEQ ID NO: 11 as the hook with regard to all 13 hooks depicted herein (see SEQ ID NOs: 11-23) where the most Klebsiella pneumoniae phages hybridize to - among others HMGUkpl . The Klebsiella pneumoniae phage labeled “HMGUkp2” binds to other four signature sequences (or complementary sequences hereto) each comprising a nucleic acid sequence, wherein the first one encodes an amino acid sequence as depicted in SEQ ID NO: 12, the second one encodes an amino acid sequence as depicted in SEQ ID NO: 15, the third one encodes an amino acid sequence as depicted in SEQ ID NO: 17, the fourth one encodes an amino acid sequence as depicted in SEQ ID NO: 19. The Pseudomonas aeruginosa phage labeled “HMGUpa3” binds to other sixth signature sequences (or complementary sequences hereto) each comprising a nucleic acid sequence, wherein the first one encodes an amino acid sequence as depicted in SEQ ID NO: 24, the second one encodes an amino acid sequence as depicted in SEQ ID NO: 27, the third one encodes an amino acid sequence as depicted in SEQ ID NO: 31 , the fourth one encodes an amino acid sequence as depicted in SEQ ID NO: 32, the fifth one encodes an amino acid sequence as depicted in SEQ ID NO: 33, the six one encodes an amino acid sequence as depicted in SEQ ID NO: 34, the signature sequence (or complementary sequence hereto) encoding an amino acid sequence as depicted in SEQ ID NO: 24 as the hook with regard to the hooks depicted in SEQ ID NOs: 24-44 where the most phages hybridize to - among others HMGUpa3. The Pseudomonas aeruginosa phage labeled “HMGUpa4” binds to other twelve signature sequences (or complementary sequences hereto) each comprising a nucleic acid sequence, wherein the first one encodes an amino acid sequence as depicted in SEQ ID NO: 25, the second one encodes an amino acid sequence as depicted in SEQ ID NO: 26, the third one encodes an amino acid sequence as depicted in SEQ ID NO: 28, the fourth one encodes an amino acid sequence as depicted in SEQ ID NO: 29, the fifth one encodes an amino acid sequence as depicted in SEQ ID NO: 30, the sixth one encodes an amino acid sequence as depicted in SEQ ID NO: 38, the seventh one encodes an amino acid sequence as depicted in SEQ ID NO: 39, the eighth one encodes an amino acid sequence as depicted in SEQ ID NO: 40, the ninth one encodes an amino acid sequence as depicted in SEQ ID NO: 41 , the tenth one encodes an amino acid sequence as depicted in SEQ ID NO: 42, the eleventh one encodes an amino acid sequence as depicted in SEQ ID NO: 43, the twelfth one encodes an amino acid sequence as depicted in SEQ ID NO: 44. All of the abovementioned proteins as depicted in SEQ ID NOs: 1-10, 11-23 and 24-44 are either highly conserved proteins of the phages infecting said bacteria, or have an important role in the bacteria lysing capacity of the phages.

Pharmaceutical composition

[0072] The present invention also comprises a pharmaceutical composition comprising the novel composition including the isolated phages as defined herein. Thus, such novel composition of the invention can also be a pharmaceutical composition. Such pharmaceutical composition may further comprise one or more of the ingredients (such as at least one excipient) as mentioned above for the composition of the invention. If at least one excipient is further comprised by the pharmaceutical composition, such excipient refers to at least one pharmaceutically acceptable excipient. Suitable pharmaceutical excipients are further described in Remington's Pharmaceutical Sciences, Mack Publishing Company, a standard reference text in this field. Said pharmaceutically acceptable excipient includes any excipient that does not itself elicit an adverse reaction harmful to the subject receiving the pharmaceutical composition. If the composition of the invention additionally comprises at least one pharmaceutically acceptable excipient, said composition refers to a pharmaceutical composition. Said pharmaceutical composition is thus used herein for therapeutic purposes. Moreover, the present invention relates to the use of said composition as disclosed herein for the preparation of a pharmaceutical composition.

[0073] In accordance with the present invention, the term "pharmaceutical composition" relates to a composition for administration to a subject as defined herein, preferably a human. Pharmaceutical compositions are usually in such a form as to allow the biological activity of the active ingredient to be effective and may therefore be administered to a subject for therapeutic use as described herein. The pharmaceutical composition can be administered in a therapeutically effective amount as defined elsewhere by inhalation, injection, infusion, or orally. The administration of said pharmaceutical composition as defined elsewhere herein may be performed intraperitoneally, intravenously, intraarterially, subcutaneously, intramuscularly, parenterally, transdermally, intraluminally, intrathecally, intranasally and/or directly into tissue due to the fact that infection with Serratia marcescens, Klebsiella pneumoniae and Pseudomonas aeruginosa can take place in different parts of the body I in multiple body sites of the subject. The pharmaceutical compositions can be administered to the subject at a suitable dose. The dosage regimen will be determined by the attending physician and by clinical factors. As is well known in the medical arts, dosages for any one patient depend upon many factors, including the patient's size, body surface area, age, the particular compound to be administered, sex, time and route of administration, general health, and other drugs being administered concurrently.

[0074] Suitable excipients are typically large, slowly metabolized macromolecules such as proteins, polysaccharides, polylactic acids, polyglycolic acids, polymeric amino acids, amino acid copolymers and lipid aggregates such as e.g. oil droplets or liposomes. The excipient used in combination with the (pharmaceutical) composition of the present invention may be water-based and forms an aqueous solution. An oil-based excipient solution is an alternative to the aqueous excipient solution.

[0075] Also, the pharmaceutical composition as defined herein may further comprise one or more adjuvants. The term "adjuvant" is used according to its well-known meaning in connection with pharmaceutical compositions. Specifically, an adjuvant is an immunological agent that modifies, preferably enhances, the effect of such composition while having few, if any, desired immunogenic effects on the immune system when given per se. Suitable adjuvants can be inorganic adjuvants such as, e.g., aluminium salts (e.g., aluminium phosphate, aluminium hydroxide), monophosphoryl lipid A, or organic adjuvants such as squalene or oil-based adjuvants, as well as virosomes.

[0076] Definitions made herein for the composition of the invention also apply mutatis mutandis to the pharmaceutical composition.

In vivo therapeutic applications

[0077] The present invention further refers to said composition or said pharmaceutical composition comprising the novel composition of the invention as defined elsewhere herein for use as a medicament. Hence, said composition or said pharmaceutical composition comprising the novel composition of the invention as defined elsewhere herein can also be used for therapy, i.e. treating or preventing a bacterial infection caused by at least any one of Pseudomonas aeruginosa, Klebsiella pneumoniae or Serratia marcescens in a subject in need thereof; such as treating or preventing a bacterial infection caused by Pseudomonas aeruginosa in a subject in need thereof, such as treating or preventing a bacterial infection caused by Klebsiella pneumoniae in a subject in need thereof, or such as treating or preventing a bacterial infection caused by Serratia marcescens in a subject in need thereof, or such as treating or preventing a bacterial infection caused by the combination of Pseudomonas aeruginosa, Klebsiella pneumoniae, and Serratia marcescen.

[0078] As such the term “treat”, “treating” or “treatment” as used herein means to reduce (slow down (lessen)), stabilize or inhibit or at least partially alleviate or abrogate the progression of the symptoms associated with the respective disease, such as a bacterial infection of a subject caused by at least any one of Pseudomonas aeruginosa, Klebsiella pneumoniae or Serratia marcescens. Thus, it includes the administration of said (pharmaceutical) composition, preferably in the form of a medicament, to a subject, defined elsewhere herein. Those in need of treatment include those already suffering from the disease, here a bacterial infection caused by at least any one of Pseudomonas aeruginosa, Klebsiella pneumoniae or Serratia marcescens as described elsewhere herein. Preferably, a treatment reduces (slows down (lessens)), stabilizes, or inhibits or at least partially alleviates or abrogates progression of a symptom that is associated with the presence and/or progression of such disease (such infection). “Treat”, “treating”, or “treatment” refers to a therapeutic treatment. In particular, in the context of the present invention, treating or treatment refers to an improvement of the symptom(s) that is associated with said bacterial infection cause by at least any one of Pseudomonas aeruginosa, Klebsiella pneumoniae or Serratia marcescens as defined elsewhere herein in a subject in need thereof. In this context, the term “treat”, “treating” or “treatment” refers to an anti-bacterial therapy that directly attacks said bacterial cells Pseudomonas aeruginosa, Klebsiella pneumoniae and/or Serratia marcescens the subject has been infected with, by the phages then infecting said bacterial cells Pseudomonas aeruginosa, Klebsiella pneumoniae and/or Serratia marcescens (is then the host cell of the phages for replication) as defined herein. Thus the (pharmaceutical) composition as defined herein may also be used as anti-bacterial therapeutic.

[0079] The term “prevent”, “preventing”, “prevention” as used herein refers to prophylactic or preventative measures, wherein the subject is to prevent an abnormal, including pathologic, condition in the organism which would then lead to the defined disease, namely said bacterial infection caused by at least any one of Pseudomonas aeruginosa, Klebsiella pneumoniae or Serratia marcescens as defined herein. In other words, said terms refer to a medical procedure whose purpose is to prevent such disease meaning inhibiting that a subject will likely suffer from any future infection caused by at least any one of Pseudomonas aeruginosa, Klebsiella pneumoniae or Serratia marcescens as defined herein. Meaning the composition comprising said phages will be given preventive to the subject not yet being infected. If the subject is then contacted and then infected by at least any one of Pseudomonas aeruginosa, Klebsiella pneumoniae or Serratia marcescens, the phages comprised in the already administered composition can then attack the bacteria right away thereby preventing a full infection caused by at least any one of Pseudomonas aeruginosa, Klebsiella pneumoniae or Serratia marcescens. As used herein, such terms also refer to the reduction in the risk of acquiring or developing such infection caused by at least any one of Pseudomonas aeruginosa, Klebsiella pneumoniae or Serratia marcescens in a patient. Those in need of the prevention include those prone to having the disease, such as the infection caused by at least any one of Pseudomonas aeruginosa, Klebsiella pneumoniae or Serratia marcescens. In other words, those who are of a risk to develop such infection and will thus probably suffer from it in the near future. Subjects suffering from an infection with SARS-CoV-2 are more likely to get such infection. Also other factors such as having a weak immune system, poor hygiene, being in the intensive care unit or being on a ventilator (breathy machine) I having a catheter for quite some time, recently having a surgery or having open wounds caused by an accident or an injury contribute to a higher risk of suffering from such infection. Thus, the (pharmaceutical) composition as defined herein may also be used as a prophylaxis, not only as a therapeutic agent for a subject as defined herein that has already been infected with at least any one of Pseudomonas aeruginosa, Klebsiella pneumoniae or Serratia marcescens.

[0080] An infection with Serratia marcescens may refer to any infection which occurs in different parts of the body I in multiple body sites of the subject, including but not limited to the lung, the blood, the brain, the kidney, the urinary tract, and also wounds. Exemplarily, an infection with Serratia marcescens may be any one of a nosocomial pneumonia, an inflammatory lung infection, a blood infection (due to the fact for example that the bacteria enter through a catheter placed in a subject’s vein), meningitis (after surgery on the brain or spine), urinary tract infection (infection of the kidneys, ureters), or a skin or wound infection. An infection with Klebsiella pneumoniae may refer to any infection which occurs in different parts of the body I in multiple body sites of the subject, including but not limited to the lung, the blood, the bladder, the kidney, the urinary tract, and also wounds. Exemplarily, an infection with Klebsiella pneumoniae may be any one of a nosocomial pneumonia, an inflammatory lung infection, a blood infection (due to the fact for example that the bacteria enter through a catheter placed in a subject’s vein), urinary tract infection (infection of the kidneys, ureters or the bladder), or a skin or wound infection. An infection with Pseudomonas aeruginosa may refer to any infection which occurs in different parts of the body I in multiple body sites of the subject, including but not limited to the lung, the blood, the brain, the bladder, the kidney, the urinary tract, and also wounds. Exemplarily, an infection with Pseudomonas aeruginosa may be any one of a nosocomial pneumonia, an inflammatory lung infection, a blood infection (due to the fact for example that the bacteria enter through a catheter placed in a subject’s vein), meningitis (after surgery on the brain or spine), urinary tract infection (infection of the kidneys, ureters or the bladder), or a skin or wound infection. Such bacteria can easily spread by direct contact with a subject already infected with at least any one of Pseudomonas aeruginosa, Klebsiella pneumoniae or Serratia marcescens, since it is found on the skin or also by contact with food, water or soil which also comprises said bacteria. As mentioned elsewhere herein, such bacteria are often susceptible or can be even resistant to many antibiotics which makes treatment of an infection with at least any one of Pseudomonas aeruginosa, Klebsiella pneumoniae or Serratia marcescens so difficult. For the purpose of distinguishing resistant from susceptible bacteria, the FEEDAP Panel defines microbiological cutoff values. Microbiological cut-off values (mg/L) are set by studying the distribution of minimum inhibitory concentrations (MICs) of the chosen antimicrobials in bacterial populations belonging to a single taxonomical unit (species or genus). The part of the population that clearly deviates from the normal susceptible populations is categorised as resistant. In particular, a bacterial cell is defined as susceptible when it is inhibited at a concentration of a specific antimicrobial equal or lower than the established cut-off value (S < x mg/L) defined by FEEDAP Panel. A bacterial cell is defined as resistant when it is not inhibited at a concentration of a specific antimicrobial higher than the established cut-off value (R > x mg/L) defined by FEEDAP Panel. The present invention may therefore also comprise the composition of the invention or the pharmaceutical composition for the use in a method of treating or preventing a bacterial infection caused by at least any one of Pseudomonas aeruginosa, Klebsiella pneumoniae or Serratia marcescens as defined herein, wherein Pseudomonas aeruginosa, Klebsiella pneumoniae and Serratia marcescens bacteria are AMR bacteria as defined elsewhere herein.

[0081] The term “subject” when used herein includes mammalian and non-mammalian subjects. Preferably the subject of the present invention is a mammal, including human, domestic and farm animals, non-human primates, and any other animal that has mammary tissue. In some embodiments the mammal is a mouse or a rat. In some embodiments the mammal is a guinea pig or a rabbit. In some embodiments the mammal is a cat. In some embodiments the mammal is a dog. In some embodiments the mammal is a monkey. In some embodiments the mammal is a horse. In preferred embodiment the mammal of the present invention is a human, most preferred an adult. Where the subject is a living human who may receive treatment for such infection as described herein, it is also addressed as a “patient”. In some embodiments the subject of the present invention suffers from said infection as described herein. In a further embodiment the subject of the present invention also suffers from an infection with SARS-CoV-2. The term “suffering” as used herein means that the subject is not any more a healthy subject. The term “healthy” means that the respective subject has no obvious or noticeable hallmarks or symptoms of the respective infection. This further means that the subject suffering from said infection is a subject “in need” of the respective treatment with the (pharmaceutical) composition as defined herein.

[0082] Such (pharmaceutical) composition is generally administered to the subject in a therapeutically effective amount. Said therapeutically effective amount is sufficient to inhibit or alleviate the symptoms of said infection. By “therapeutic effect” or “therapeutically effective” is meant that the conjugate for use will elicit the biological or medical response of a tissue, system, animal or human that is being sought by the researcher, veterinarian, medical doctor or other clinician. The term “therapeutically effective” further refers to the inhibition of factors causing or contributing to the infection. The term “therapeutically effective amount” includes that the amount of the composition when administered is sufficient to significantly improve the progression of the infection being treated or to prevent development of said infection. According to a preferred embodiment, the therapeutic effective amount is sufficient to alleviate or heal said infection as defined herein.

[0083] The therapeutically effective amount will vary depending on the (pharmaceutical) composition of the present invention, the infection as described herein and its severity and on individual factors of the subject and/or also how the administration works. Therefore, the (pharmaceutical) composition of the present invention will not in all cases turn out to be therapeutically effective, because the method disclosed herein cannot provide a 100% safe prediction whether or not a subject may be responsive to the (pharmaceutical) composition, since individual factors are involved as well. It is to expect that age, body weight, general health, sex, diet, drug interaction and the like may have a general influence as to whether or not the (pharmaceutical) composition for use in the treatment of a subject suffering from said infection will be therapeutically effective. [0084] The term “administering” or “administered” or “administration” used throughout various aspects of the present invention means that the (pharmaceutical) composition as defined herein are given to the respective subject in an appropriate form and dose and using appropriate measures. The administration of the composition according to the present invention can be carried out by any method known in the art.

[0085] In alternative embodiments, the (pharmaceutical) composition for the use in the treatment of said infection may also be administered in combination with an additional therapeutic agent (drug). Drugs or therapeutic agents useful in this regard include without limitation drug-like molecules, proteins, peptides, and small molecules. Protein therapeutic agents include, without limitation peptides, enzymes, antibodies, structural proteins, receptors and other cellular or circulating proteins as well as fragments and derivatives thereof, preferably an additional therapeutic agent I drug in the context of the present invention may be a drug for the use in an infection caused by at least any one of Pseudomonas aeruginosa, Klebsiella pneumoniae or Serratia marcescens as described elsewhere herein, especially for combinatorial therapy in said infection. Said combination according to the present invention can be administered as a combined formulation or separate from each other.

[0086] The present invention also provides for a method of treating or preventing a bacterial infection caused by at least any one of Pseudomonas aeruginosa, Klebsiella pneumoniae or Serratia marcescens in a subject in need thereof, the method comprising administering a therapeutically effective amount of said composition or said pharmaceutical composition to a subject in need thereof. Also comprised herein is the use of said (pharmaceutical) composition as defined herein for the manufacture of a medicament for therapeutic application in a bacterial infection caused by at least any one of Pseudomonas aeruginosa, Klebsiella pneumoniae or Serratia marcescens in a subject. The definitions and embodiments made with regard to the first and second medical uses may also be applied, where necessary, in these embodiments as well.

Kits

[0087] The present invention also comprises a kit comprising the composition comprising the isolated phages of the present invention or said pharmaceutical composition comprising such composition. Thus, when a kit comprises said (pharmaceutical) composition, said compositions may be provided in a vial or a container, preferably also comprising in said vial or container at least one excipient as defined herein. Further, said kit may be associated with a notice in the form prescribed by a governmental agency regulating the manufacture, use or sale of pharmaceuticals or biological products, reflecting approval by the agency of the manufacture, use or sale of the product for human administration or diagnostics. Said kit may comprise the (pharmaceutical) composition, preferably in a vial or container, in dried form, such as a lyophilized, air-dried, or spray-dried form (in form of a powder), for later reconstitution into a liquid form or other form prior to use. Further, said kit may also comprise the (pharmaceutical) composition, preferably in a vial or container, in a frozen state, being thawed prior to use. Further, said kit may also comprise the (pharmaceutical) composition, preferably in a vial or container, in liquid state.

[0088] The present invention also comprises a kit comprising the hooks as defined elsewhere herein. In detail, the present invention comprises a kit comprising i) a first nucleic acid sequence (“a first hook” which is used to isolate Serratia marcescens phages - “first phages” - as defined herein), which is at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, at least 98%, at least 99% or 100% identical to a nucleic acid sequence encoding an amino acid sequence as depicted in at least any one selected from the group consisting of SEQ ID NOs: 1-10, or a complementary sequence thereof; ii) a second nucleic acid sequence (“a second hook” which is used to isolate Klebsiella pneumoniae phages - “second phages” - as defined herein), which is at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, at least 98%, at least 99% or 100% identical to a nucleic acid sequence encoding an amino acid sequence as depicted in at least any one selected from the group consisting of SEQ ID NOs: 11-23, or a complementary sequence thereof; and iii) a third nucleic acid sequence (“a third hook” which is used to isolate Pseudomonas aeruginosa phages - “third phages” - as defined herein), which is at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, at least 98%, at least 99% or 100% identical to a nucleic acid sequence encoding an amino acid sequence as depicted in at least any one selected from the group consisting of SEQ ID NOs: 24-44, or a complementary sequence thereof.

[0089] In one embodiment of the invention, the present invention comprises a kit comprising i) a first nucleic acid sequence, which is at least 60% identical to a nucleic acid sequence encoding an amino acid sequence as depicted in at least any one selected from the group consisting of SEQ ID NOs: 1-10 (preferably SEQ ID NO: 1), or a complementary sequence thereof; ii) a second nucleic acid sequence, which is at least 60% identical to a nucleic acid sequence encoding an amino acid sequence as depicted in at least any one selected from the group consisting of SEQ ID NOs: 11-23 (preferably SEQ ID NO: 11), or a complementary sequence thereof; and iii) a third nucleic acid sequence, which is at least 60% identical to a nucleic acid sequence encoding an amino acid sequence as depicted in at least any one selected from the group consisting of SEQ ID NOs: 24-44 (preferably SEQ ID NO: 24), or a complementary sequence thereof. In one embodiment of the invention, the present invention comprises a kit comprising i) a first nucleic acid sequence, which is at least 70% identical to a nucleic acid sequence encoding an amino acid sequence as depicted in at least any one selected from the group consisting of SEQ ID NOs: 1- 10 (preferably SEQ ID NO: 1), or a complementary sequence thereof; ii) a second nucleic acid sequence, which is at least 70% identical to a nucleic acid sequence encoding an amino acid sequence as depicted in at least any one selected from the group consisting of SEQ ID NOs: 11- 23 (preferably SEQ ID NO: 11), or a complementary sequence thereof; and iii) a third nucleic acid sequence, which is at least 70% identical to a nucleic acid sequence encoding an amino acid sequence as depicted in at least any one selected from the group consisting of SEQ ID NOs: 24- 44 (preferably SEQ ID NO: 24), or a complementary sequence thereof. In one embodiment of the invention, the present invention comprises a kit comprising i) a first nucleic acid sequence, which is at least 80% identical to a nucleic acid sequence encoding an amino acid sequence as depicted in at least any one selected from the group consisting of SEQ ID NOs: 1-10 (preferably SEQ ID NO: 1), or a complementary sequence thereof; ii) a second nucleic acid sequence, which is at least 80% identical to a nucleic acid sequence encoding an amino acid sequence as depicted in at least any one selected from the group consisting of SEQ ID NOs: 11-23 (preferably SEQ ID NO: 11), or a complementary sequence thereof; and iii) a third nucleic acid sequence, which is at least 80% identical to a nucleic acid sequence encoding an amino acid sequence as depicted in at least any one selected from the group consisting of SEQ ID NOs: 24-44 (preferably SEQ ID NO: 24), or a complementary sequence thereof. In one embodiment of the invention, the present invention comprises a kit comprising i) a first nucleic acid sequence, which is at least 90% identical to a nucleic acid sequence encoding an amino acid sequence as depicted in at least any one selected from the group consisting of SEQ ID NOs: 1-10 (preferably SEQ ID NO: 1), or a complementary sequence thereof; ii) a second nucleic acid sequence, which is at least 90% identical to a nucleic acid sequence encoding an amino acid sequence as depicted in at least any one selected from the group consisting of SEQ ID NOs: 11-23 (preferably SEQ ID NO: 11), or a complementary sequence thereof; and iii) a third nucleic acid sequence, which is at least 90% identical to a nucleic acid sequence encoding an amino acid sequence as depicted in at least any one selected from the group consisting of SEQ ID NOs: 24-44 (preferably SEQ ID NO: 24), or a complementary sequence thereof. In one embodiment of the invention, the present invention comprises a kit comprising i) a first nucleic acid sequence, which is at least 95% identical to a nucleic acid sequence encoding an amino acid sequence as depicted in at least any one selected from the group consisting of SEQ ID NOs: 1-10 (preferably SEQ ID NO: 1), or a complementary sequence thereof; ii) a second nucleic acid sequence, which is at least 95% identical to a nucleic acid sequence encoding an amino acid sequence as depicted in at least any one selected from the group consisting of SEQ ID NOs: 11-23 (preferably SEQ ID NO: 11), or a complementary sequence thereof; and iii) a third nucleic acid sequence, which is at least 95% identical to a nucleic acid sequence encoding an amino acid sequence as depicted in at least any one selected from the group consisting of SEQ ID NOs: 24-44 (preferably SEQ ID NO: 24), or a complementary sequence thereof.

[0090] In one embodiment of the invention, the present invention comprises a kit comprising i) a first nucleic acid sequence, which is at least 60% identical to a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 1 , or a complementary sequence thereof; ii) a second nucleic acid sequence, which is at least 60% identical to a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 11 , or a complementary sequence thereof, and another second nucleic acid sequence, which is at least 60% identical to a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 12, or a complementary sequence thereof; and iii) a third nucleic acid sequence, which is at least 60% identical to a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 24, or a complementary sequence thereof, and another third nucleic acid sequence, which is at least 60% identical to a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 25, or a complementary sequence thereof. In one embodiment of the invention, the present invention comprises a kit comprising i) a first nucleic acid sequence, which is at least 70% identical to a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 1 , or a complementary sequence thereof; ii) a second nucleic acid sequence, which is at least 70% identical to a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 11 , or a complementary sequence thereof, and another second nucleic acid sequence, which is at least 70% identical to a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 12, or a complementary sequence thereof; and iii) a third nucleic acid sequence, which is at least 70% identical to a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 24, or a complementary sequence thereof, and another third nucleic acid sequence, which is at least 70% identical to a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 25, or a complementary sequence thereof. In one embodiment of the invention, the present invention comprises a kit comprising i) a first nucleic acid sequence, which is at least 80% identical to a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 1 , or a complementary sequence thereof; ii) a second nucleic acid sequence, which is at least 80% identical to a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 11 , or a complementary sequence thereof, and another second nucleic acid sequence, which is at least 80% identical to a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 12, or a complementary sequence thereof; and iii) a third nucleic acid sequence, which is at least 80% identical to a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 24, or a complementary sequence thereof, and another third nucleic acid sequence, which is at least 80% identical to a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 25, or a complementary sequence thereof. In one embodiment of the invention, the present invention comprises a kit comprising i) a first nucleic acid sequence, which is at least 90% identical to a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 1 , or a complementary sequence thereof; ii) a second nucleic acid sequence, which is at least 90% identical to a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 11 , or a complementary sequence thereof, and another second nucleic acid sequence, which is at least 90% identical to a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 12, or a complementary sequence thereof; and iii) a third nucleic acid sequence, which is at least 90% identical to a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 24, or a complementary sequence thereof, and another third nucleic acid sequence, which is at least 90% identical to a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 25, or a complementary sequence thereof. In one embodiment of the invention, the present invention comprises a kit comprising i) a first nucleic acid sequence, which is at least 95% identical to a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 1 , or a complementary sequence thereof; ii) a second nucleic acid sequence, which is at least 95% identical to a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 11 , or a complementary sequence thereof, and another second nucleic acid sequence, which is at least 95% identical to a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 12, or a complementary sequence thereof; and iii) a third nucleic acid sequence, which is at least 95% identical to a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 24, or a complementary sequence thereof, and another third nucleic acid sequence, which is at least 95% identical to a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 25, or a complementary sequence thereof.

[0091] Thus, when a kit comprises said hooks, said hooks may be provided in a vial or a container, preferably also comprising in said vial or container at least one excipient as defined herein. The kit may comprise a combination of hooks as defined elsewhere herein, preferably SEQ ID NOs: 1 , 11 and 24, more preferably SEQ ID NOs: 1 , 11 , 12, 24 and 25. Such hooks (combination of hooks) can either be comprised separately in different vials or containers or comprised all together in one vial or container. Further, said kits may be associated with a notice in the form prescribed by a governmental agency regulating the manufacture, use or sale of pharmaceuticals or biological products, reflecting approval by the agency of the manufacture, use or sale of the product for human administration or diagnostics. Said kits may comprise the hook(s), preferably in a vial or container, in dried form, such as a lyophilized, air-dried, or spray-dried form (in form of a powder), for later reconstitution into a liquid form or other form prior to use. Further, said kits may also comprise the hook(s), preferably in a vial or container, in a frozen state, being thawed prior to use. Further, said kits may also comprise the hook(s), preferably in a vial or container, in liquid state.

[0092] Additionally, the kit according to the present invention either comprising the (pharmaceutical) composition or the hooks may also comprise a detectable label. The present invention may thus comprise the kit comprising the hooks as defined herein, wherein each of the nucleic acid sequences as defined above (which refer to the hooks) are conjugated to a detectable label. It is also comprised herein, that such nucleic acid sequences may be attached to a detectable label or just labeled. A “detectable label” as used herein may refer to a compound capable of targeting said nucleic acids and which can then be detected by any detection methods known to a person skilled in the art, which depends certainly on the label being used. Said label may be selected from the group consisting of a biotin, a tag, a fluorophore, a radioactive phosphate (P³²) or radioactive sulfate (S³⁵), and any active site probe, i.e. a detectable moiety suitable for the labeling and detection of said nucleic acids. The nucleic acids may also be conjugated to a combination of any one of the detectable labels mentioned above. For example, the nucleic acids may be conjugated to a detectable fluorophore and further labeled with a radioactive phosphate.

[0093] When the label is a biotin, nucleotides of the nucleic acid sequences comprised by said nucleic acids may be labeled with biotin. When the label is a tag, an oligohistidine-tag (Hise tag) may be used. In this context, the nucleic acid may be modified with for example nitrilotriacetate (NTA) which has high affinity to a His-tag. When the label is a fluorophore (also called fluorochrome or chromophore) in the present invention it may be any DNA fluorescent dye such as but not limited to Acridine Orange hydrochloride, 7-Aminoactinomycin D, DAPI, Hoechst 3342, Hoechst Janelia Fluor 526, Hoechst Janelia Fluor 646, Nucleic Acid Dye Green I, propidium iodide, or one of a fluorescent dye such as but not limited to Fluorescein (FITC) , Alexa Fluor 350, 405, 488, 532, 546, 555, 568, 594, 647, 680, 700, 750, Pacific Blue, Coumarin, Pacific Green, Cy3, Texas Red, PE, PerCP-Cy5, PE-Cy7, Pacific Orange, or a fluorescent protein label such as R-PE or APC, or an expressed fluorescent protein such as CFP, EGFP, GFP or RFP. Preferably, when the label is a fluorophore any DNA fluorescent dye is used. The labeling with such fluorophore (preferably any DNA fluorescent dye) may be performed by labeling the nucleotides of the nucleic acids as it is known to a person skilled in the art. When the label is a radioactive phosphate (P³²) or sulfate (S³⁵), one of the incorporated nucleotides may be radiolabeled on the alpha phosphate position.

[0094] Said nucleic acids may be labeled at their 5' end (DNA 5’ end labeling), their 3' end (DNA 3’ end labeling), or throughout the nucleic acid depending on the application (for example labeling by PCR). For hybridization as outlined herein, it is preferred to generate high specific activity probes with such label distributed throughout the nucleic acid, through techniques such as nick translation, random priming, by PCR or in vitro transcription using labeled dNTPs or NTPs. The conjugation (attachment) of a label (preferably a fluorophore, even more preferably any DNA fluorescent dye) may be either direct (without any linker) or indirect via a linker. Thus, it is also comprised herein that the nucleic acids may be conjugated via a linker I linked to a detectable label as defined herein. Said conjugation to the detectable label may also be covalently as defined elsewhere herein. Thus, it is also comprised herein that the nucleic acids are directly or indirectly conjugated to a detectable label, preferably covalently. The term “covalently” refers to covalent bonds that are typically formed by the sharing of electron pairs between atoms. In accordance with the present invention and when the term “covalently” is used, a covalent bond is formed between the nucleic acids and the label as defined elsewhere herein by use of a linker of at least 1 amino acid in length as defined above.

[0095] In some embodiments, said label may also be comprised in the one or more containers or vials of the kit as defined above comprising said (pharmaceutical) composition or in the one or more containers or vials of the kit as defined above comprising said hooks; or in additional one or more vials or containers of said kits, preferably further comprising in said one or more vials or containers any excipient suitable for said label to be mixed with I contacted with.

[0096] In some embodiments, said hook(s) may also be comprised in the same kit which comprises said (pharmaceutical) composition as defined above (with or without said label within the same kit). All definitions made throughout the application regarding the composition and/or the hooks may be applicable to the kits defined herein.

In vitro applications

[0097] The present invention also comprises a method of preparing a composition comprising isolated phages, the method comprising the following steps of first providing a sample which comprises the phages to be isolated from. Such step may also be optional. Such sample may be any one of a naturally environmental sample, a clinical sample, a wastewater treatment plant sample which includes but is not limited to a sewage water sample, or a hospital waste resources sample. In a next step, said first, second and third phages as defined herein are isolated from said sample as defined herein using at least any one of the corresponding hooks of the invention as defined herein. “Targeted isolating” or “targeted isolation” (“hook isolation”) may be carried out by any method known in the art suitable to isolate phages based on selected gene or nucleic acid molecule sequences. Such step may also include a viral tagging (also called phage labeling) step as defined by WO2021/048257 incorporated by references herein resulting in the phages being labeled, wherein the labelling may be selected from the group consisting of fluorescent labelling, antibody labelling and radioactive labelling (preferably fluorescent labelling). Then, target bacteria (in the context of the invention Pseudomonas aeruginosa, Klebsiella pneumoniae and Serratia marcescens) may be added to said sample comprising the already labeled phages, whereby said labeled phages come into contact with the target bacteria. This may be followed by single-cell sorting of such bacteria-phages into single pairs. As a general example in accordance with the present invention, single phage-bacteria pairs may then be sorted onto solid bacterial lawns, or liquid growth media (e.g. in multi-well plate), and incubated under conditions allowing phage infection take place.

[0098] Agar from the infected area (plaque) in the former approach, or aliquots of phage suspensions in the latter approach may then be transferred to a vial (e.g. to 2^nd multi-well plates) containing premixed (e.g., barcoded) primer(s), which refer to at least any one of the defined hooks already designed before. Such vial may also comprise besides the primer(s) a PCR Master mix for PCR or qPCR. This results in isolating the particular Pseudomonas aeruginosa, Klebsiella pneumoniae and Serratia marcescens phages which hybridize to the particular hooks (primers in the qPCR) being used for said targeted phage isolation.

[0099] For the targeted phage isolation to be performed within the method of the invention, such first phages comprise a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in at least any one selected from the group consisting of SEQ ID NOs: 1-10, preferably SEQ ID NO: 1 , and wherein the nucleic acid comprises a nucleic acid sequence, which is at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, at least 98%, at least 99% or 100% identical to the nucleic acid sequence encoding the amino acid sequence as depicted in at least any one selected from the group consisting of SEQ ID NOs: 1-10, preferably SEQ ID NO: 1 , which refer(s) to the defined hook(s) being used for targeted phage isolation of Serratia marcescens phages. Alternatively, such phages may comprise a nucleic acid being part of its genome, wherein the nucleic acid comprises a nucleic acid sequence, which is at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, at least 98%, at least 99% or 100% identical to a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 2. In a further embodiment, such phages may comprise a nucleic acid being part of its genome, wherein the nucleic acid comprises a nucleic acid sequence, which is at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, at least 98%, at least 99% or 100% identical to a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 3. In another embodiment, such phages may comprise a nucleic acid being part of its genome, wherein the nucleic acid comprises a nucleic acid sequence, which is at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, at least 98%, at least 99% or 100% identical to a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 4. In another embodiment, such phages may comprise a nucleic acid being part of its genome, wherein the nucleic acid comprises a nucleic acid sequence, which is at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, at least 98%, at least 99% or 100% identical to a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 5. In another embodiment, such phages may comprise a nucleic acid being part of its genome, wherein the nucleic acid comprises a nucleic acid sequence, which is at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, at least 98%, at least 99% or 100% identical to a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 6. In another embodiment, such phages may comprise a nucleic acid being part of its genome, wherein the nucleic acid comprises a nucleic acid sequence, which is at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, at least 98%, at least 99% or 100% identical to a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 7. In another embodiment, such phages may comprise a nucleic acid being part of its genome, wherein the nucleic acid comprises a nucleic acid sequence, which is at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, at least 98%, at least 99% or 100% identical to a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 8. In another embodiment, such phages may comprise a nucleic acid being part of its genome, wherein the nucleic acid comprises a nucleic acid sequence, which is at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, at least 98%, at least 99% or 100% identical to a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 9. In another embodiment, such phages may comprise a nucleic acid being part of its genome, wherein the nucleic acid comprises a nucleic acid sequence, which is at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, at least 98%, at least 99% or 100% identical to a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 10.

[00100] For the targeted phage isolation to be performed within the method of the invention, such second phages comprise a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in at least any one selected from the group consisting of SEQ ID NOs: 11-23, preferably SEQ ID NO: 11 , and wherein the nucleic acid comprises a nucleic acid sequence, which is at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, at least 98%, at least 99% or 100% identical to the nucleic acid sequence encoding the amino acid sequence as depicted in at least any one selected from the group consisting of SEQ ID NOs: 11-23, preferably SEQ ID NO: 11 , which refer(s) to the defined hook(s) being used for targeted phage isolation of Klebsiella pneumoniae phages. In another embodiment, such phages may comprise a nucleic acid being part of its genome, wherein the nucleic acid comprises a nucleic acid sequence, which is at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, at least 98%, at least 99% or 100% identical to a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 12. In another embodiment, such phages may comprise a nucleic acid being part of its genome, wherein the nucleic acid comprises a nucleic acid sequence, which is at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, at least 98%, at least 99% or 100% identical to a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 13. In another embodiment, such phages may comprise a nucleic acid being part of its genome, wherein the nucleic acid comprises a nucleic acid sequence, which is at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, at least 98%, at least 99% or 100% identical to a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 14. In another embodiment, such phages may comprise a nucleic acid being part of its genome, wherein the nucleic acid comprises a nucleic acid sequence, which is at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, at least 98%, at least 99% or 100% identical to a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 15. In another embodiment, such phages may comprise a nucleic acid being part of its genome, wherein the nucleic acid comprises a nucleic acid sequence, which is at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, at least 98%, at least 99% or 100% identical to a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 16. In another embodiment, such phages may comprise a nucleic acid being part of its genome, wherein the nucleic acid comprises a nucleic acid sequence, which is at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, at least 98%, at least 99% or 100% identical to a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 17. In another embodiment, such phages may comprise a nucleic acid being part of its genome, wherein the nucleic acid comprises a nucleic acid sequence, which is at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, at least 98%, at least 99% or 100% identical to a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 18. In another embodiment, such phages may comprise a nucleic acid being part of its genome, wherein the nucleic acid comprises a nucleic acid sequence, which is at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, at least 98%, at least 99% or 100% identical to a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 19. In another embodiment, such phages may comprise a nucleic acid being part of its genome, wherein the nucleic acid comprises a nucleic acid sequence, which is at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, at least 98%, at least 99% or 100% identical to a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 20. In another embodiment, such phages may comprise a nucleic acid being part of its genome, wherein the nucleic acid comprises a nucleic acid sequence, which is at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, at least 98%, at least 99% or 100% identical to a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 21. In another embodiment, such phages may comprise a nucleic acid being part of its genome, wherein the nucleic acid comprises a nucleic acid sequence, which is at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, at least 98%, at least 99% or 100% identical to a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 22. In another embodiment, such phages may comprise a nucleic acid being part of its genome, wherein the nucleic acid comprises a nucleic acid sequence, which is at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, at least 98%, at least 99% or 100% identical to a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 23. [00101] For the targeted phage isolation to be performed within the method of the invention, such third phages comprise a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence comprising a nucleic acid sequence encoding an amino acid sequence as depicted in at least any one selected from the group consisting of SEQ ID NOs: 24-44, preferably SEQ ID NO: 24, and wherein the nucleic acid comprises a nucleic acid sequence, which is at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, at least 98%, at least 99% or 100% identical to the nucleic acid sequence encoding the amino acid sequence as depicted in at least any one selected from the group consisting of SEQ ID NOs: 24-44, preferably SEQ ID NO: 24, which refer(s) to the defined hook(s) being used for targeted phage isolation of Pseudomonas aeruginosa phages. In another embodiment, such phages may comprise a nucleic acid being part of its genome, wherein the nucleic acid comprises a nucleic acid sequence, which is at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, at least 98%, at least 99% or 100% identical to a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 25. In another embodiment, such phages may comprise a nucleic acid being part of its genome, wherein the nucleic acid comprises a nucleic acid sequence, which is at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, at least 98%, at least 99% or 100% identical to a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 26. In another embodiment, such phages may comprise a nucleic acid being part of its genome, wherein the nucleic acid comprises a nucleic acid sequence, which is at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, at least 98%, at least 99% or 100% identical to a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 27. In another embodiment, such phages may comprise a nucleic acid being part of its genome, wherein the nucleic acid comprises a nucleic acid sequence, which is at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, at least 98%, at least 99% or 100% identical to a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 28. In another embodiment, such phages may comprise a nucleic acid being part of its genome, wherein the nucleic acid comprises a nucleic acid sequence, which is at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, at least 98%, at least 99% or 00% identical to a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 29. In another embodiment, such phages may comprise a nucleic acid being part of its genome, wherein the nucleic acid comprises a nucleic acid sequence, which is at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, at least 98%, at least 99% or 100% identical to a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 30. In another embodiment, such phages may comprise a nucleic acid being part of its genome, wherein the nucleic acid comprises a nucleic acid sequence, which is at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, at least 98%, at least 99% or 100% identical to a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 31. In another embodiment, such phages may comprise a nucleic acid being part of its genome, wherein the nucleic acid comprises a nucleic acid sequence, which is at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, at least 98%, at least 99% or 100% identical to a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 32. In another embodiment, such phages may comprise a nucleic acid being part of its genome, wherein the nucleic acid comprises a nucleic acid sequence, which is at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, at least 98%, at least 99% or 100% identical to a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 33. In another embodiment, such phages may comprise a nucleic acid being part of its genome, wherein the nucleic acid comprises a nucleic acid sequence, which is at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, at least 98%, at least 99% or 100% identical to a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 34. In another embodiment, such phages may comprise a nucleic acid being part of its genome, wherein the nucleic acid comprises a nucleic acid sequence, which is at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, at least 98%, at least 99% or 100% identical to a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 35. In another embodiment, such phages may comprise a nucleic acid being part of its genome, wherein the nucleic acid comprises a nucleic acid sequence, which is at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, at least 98%, at least 99% or 100% identical to a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 36. In another embodiment, such phages may comprise a nucleic acid being part of its genome, wherein the nucleic acid comprises a nucleic acid sequence, which is at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, at least 98%, at least 99% or 100% identical to a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 37. In another embodiment, such phages may comprise a nucleic acid being part of its genome, wherein the nucleic acid comprises a nucleic acid sequence, which is at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, at least 98%, at least 99% or 100% identical to a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 38. In another embodiment, such phages may comprise a nucleic acid being part of its genome, wherein the nucleic acid comprises a nucleic acid sequence, which is at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, at least 98%, at least 99% or 100% identical to a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 39. In another embodiment, such phages may comprise a nucleic acid being part of its genome, wherein the nucleic acid comprises a nucleic acid sequence, which is at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, at least 98%, at least 99% or 100% identical to a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 40. In another embodiment, such phages may comprise a nucleic acid being part of its genome, wherein the nucleic acid comprises a nucleic acid sequence, which is at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, at least 98%, at least 99% or 100% identical to a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 41. In another embodiment, such phages may comprise a nucleic acid being part of its genome, wherein the nucleic acid comprises a nucleic acid sequence, which is at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, at least 98%, at least 99% or 100% identical to a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 42. In another embodiment, such phages may comprise a nucleic acid being part of its genome, wherein the nucleic acid comprises a nucleic acid sequence, which is at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, at least 98%, at least 99% or 100% identical to a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 43. In another embodiment, such phages may comprise a nucleic acid being part of its genome, wherein the nucleic acid comprises a nucleic acid sequence, which is at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, at least 98%, at least 99% or 100% identical to a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 44.

[00102] In a preferred embodiment, the present invention comprises a method of preparing a composition comprising isolated phages, the method comprising targeted isolating of phages comprised in a provided sample as defined herein, wherein i) the first phages comprise a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence hereto comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 1 and wherein the nucleic acid comprises a nucleic acid sequence, which is at least 60% identical to the nucleic acid sequence encoding the amino acid sequence as depicted in SEQ ID NO: 1 ; ii) the second phages comprise a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence hereto comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 11 and wherein the nucleic acid comprises a nucleic acid sequence, which is at least 60% identical to the nucleic acid sequence encoding the amino acid sequence as depicted in SEQ ID NO: 11 ; and iii) the third phages comprise a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence hereto comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 24 and wherein the nucleic acid comprises a nucleic acid sequence, which is at least 60% identical to the nucleic acid sequence encoding the amino acid sequence as depicted in SEQ ID NO: 24. In a preferred embodiment, the present invention comprises a method of preparing a composition comprising isolated phages, the method comprising targeted isolating of phages comprised in a provided sample as defined herein, wherein i) the first phages comprise a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence hereto comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 1 and wherein the nucleic acid comprises a nucleic acid sequence, which is at least 70% identical to the nucleic acid sequence encoding the amino acid sequence as depicted in SEQ ID NO: 1 ; ii) the second phages comprise a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence hereto comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 11 and wherein the nucleic acid comprises a nucleic acid sequence, which is at least 70% identical to the nucleic acid sequence encoding the amino acid sequence as depicted in SEQ ID NO: 11; and iii) the third phages comprise a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence hereto comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 24 and wherein the nucleic acid comprises a nucleic acid sequence, which is at least 70% identical to the nucleic acid sequence encoding the amino acid sequence as depicted in SEQ ID NO: 24. In a preferred embodiment, the present invention comprises a method of preparing a composition comprising isolated phages, the method comprising targeted isolating of phages comprised in a provided sample as defined herein, wherein i) the first phages comprise a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence hereto comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 1 and wherein the nucleic acid comprises a nucleic acid sequence, which is at least 80% identical to the nucleic acid sequence encoding the amino acid sequence as depicted in SEQ ID NO: 1 ; ii) the second phages comprise a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence hereto comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 11 and wherein the nucleic acid comprises a nucleic acid sequence, which is at least 80% identical to the nucleic acid sequence encoding the amino acid sequence as depicted in SEQ ID NO: 11 ; and iii) the third phages comprise a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence hereto comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 24 and wherein the nucleic acid comprises a nucleic acid sequence, which is at least 80% identical to the nucleic acid sequence encoding the amino acid sequence as depicted in SEQ ID NO: 24. In a preferred embodiment, the present invention comprises a method of preparing a composition comprising isolated phages, the method comprising targeted isolating of phages comprised in a provided sample as defined herein, wherein i) the first phages comprise a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence hereto comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 1 and wherein the nucleic acid comprises a nucleic acid sequence, which is at least 90% identical to the nucleic acid sequence encoding the amino acid sequence as depicted in SEQ ID NO: 1 ; ii) the second phages comprise a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence hereto comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 11 and wherein the nucleic acid comprises a nucleic acid sequence, which is at least 90% identical to the nucleic acid sequence encoding the amino acid sequence as depicted in SEQ ID NO: 11; and iii) the third phages comprise a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence hereto comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 24 and wherein the nucleic acid comprises a nucleic acid sequence, which is at least 90% identical to the nucleic acid sequence encoding the amino acid sequence as depicted in SEQ ID NO: 24. In a preferred embodiment, the present invention comprises a method of preparing a composition comprising isolated phages, the method comprising targeted isolating of phages comprised in a provided sample as defined herein, wherein i) the first phages comprise a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence hereto comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 1 and wherein the nucleic acid comprises a nucleic acid sequence, which is at least 95% identical to the nucleic acid sequence encoding the amino acid sequence as depicted in SEQ ID NO: 1 ; ii) the second phages comprise a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence hereto comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 11 and wherein the nucleic acid comprises a nucleic acid sequence, which is at least 95% identical to the nucleic acid sequence encoding the amino acid sequence as depicted in SEQ ID NO: 11 ; and iii) the third phages comprise a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence hereto comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 24 and wherein the nucleic acid comprises a nucleic acid sequence, which is at least 95% identical to the nucleic acid sequence encoding the amino acid sequence as depicted in SEQ ID NO: 24.

[00103] In a preferred embodiment, the present invention comprises a method of preparing a composition comprising isolated phages, the method comprising targeted isolating of phages comprised in a provided sample as defined herein, wherein i) the first phages comprise a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence hereto comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 1 and wherein the nucleic acid comprises a nucleic acid sequence, which is at least 60% identical to the nucleic acid sequence encoding the amino acid sequence as depicted in SEQ ID NO: 1 ; ii) the second phages comprise a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence hereto comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 11 and wherein the nucleic acid comprises a nucleic acid sequence, which is at least 60% identical to the nucleic acid sequence encoding the amino acid sequence as depicted in SEQ ID NO: 11 ; and other second phages comprise a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence hereto comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 12 and wherein the nucleic acid comprises a nucleic acid sequence, which is at least 60% identical to the nucleic acid sequence encoding the amino acid sequence as depicted in SEQ ID NO: 12; and iii) the third phages comprise a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence hereto comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 24 and wherein the nucleic acid comprises a nucleic acid sequence, which is at least 60% identical to the nucleic acid sequence encoding the amino acid sequence as depicted in SEQ ID NO: 24; and other third phages comprise a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence hereto comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 25 and wherein the nucleic acid comprises a nucleic acid sequence, which is at least 60% identical to the nucleic acid sequence encoding the amino acid sequence as depicted in SEQ ID NO: 25. In a preferred embodiment, the present invention comprises a method of preparing a composition comprising isolated phages, the method comprising targeted isolating of phages comprised in a provided sample as defined herein, wherein i) the first phages comprise a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence hereto comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 1 and wherein the nucleic acid comprises a nucleic acid sequence, which is at least 70% identical to the nucleic acid sequence encoding the amino acid sequence as depicted in SEQ ID NO: 1 ; ii) the second phages comprise a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence hereto comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 11 and wherein the nucleic acid comprises a nucleic acid sequence, which is at least 70% identical to the nucleic acid sequence encoding the amino acid sequence as depicted in SEQ ID NO: 11 ; and other second phages comprise a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence hereto comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 12 and wherein the nucleic acid comprises a nucleic acid sequence, which is at least 70% identical to the nucleic acid sequence encoding the amino acid sequence as depicted in SEQ ID NO: 12; and iii) the third phages comprise a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence hereto comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 24 and wherein the nucleic acid comprises a nucleic acid sequence, which is at least 70% identical to the nucleic acid sequence encoding the amino acid sequence as depicted in SEQ ID NO: 24; and other third phages comprise a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence hereto comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 25 and wherein the nucleic acid comprises a nucleic acid sequence, which is at least 70% identical to the nucleic acid sequence encoding the amino acid sequence as depicted in SEQ ID NO: 25. In a preferred embodiment, the present invention comprises a method of preparing a composition comprising isolated phages, the method comprising targeted isolating of phages comprised in a provided sample as defined herein, wherein i) the first phages comprise a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence hereto comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 1 and wherein the nucleic acid comprises a nucleic acid sequence, which is at least 80% identical to the nucleic acid sequence encoding the amino acid sequence as depicted in SEQ ID NO: 1 ; ii) the second phages comprise a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence hereto comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 11 and wherein the nucleic acid comprises a nucleic acid sequence, which is at least 80% identical to the nucleic acid sequence encoding the amino acid sequence as depicted in SEQ ID NO: 11 ; and other second phages comprise a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence hereto comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 12 and wherein the nucleic acid comprises a nucleic acid sequence, which is at least 80% identical to the nucleic acid sequence encoding the amino acid sequence as depicted in SEQ ID NO: 12; and iii) the third phages comprise a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence hereto comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 24 and wherein the nucleic acid comprises a nucleic acid sequence, which is at least 80% identical to the nucleic acid sequence encoding the amino acid sequence as depicted in SEQ ID NO: 24; and other third phages comprise a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence hereto comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 25 and wherein the nucleic acid comprises a nucleic acid sequence, which is at least 80% identical to the nucleic acid sequence encoding the amino acid sequence as depicted in SEQ ID NO: 25. In a preferred embodiment, the present invention comprises a method of preparing a composition comprising isolated phages, the method comprising targeted isolating of phages comprised in a provided sample as defined herein, wherein i) the first phages comprise a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence hereto comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 1 and wherein the nucleic acid comprises a nucleic acid sequence, which is at least 90% identical to the nucleic acid sequence encoding the amino acid sequence as depicted in SEQ ID NO: 1 ; ii) the second phages comprise a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence hereto comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 11 and wherein the nucleic acid comprises a nucleic acid sequence, which is at least 90% identical to the nucleic acid sequence encoding the amino acid sequence as depicted in SEQ ID NO: 11 ; and other second phages comprise a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence hereto comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 12 and wherein the nucleic acid comprises a nucleic acid sequence, which is at least 90% identical to the nucleic acid sequence encoding the amino acid sequence as depicted in SEQ ID NO: 12; and iii) the third phages comprise a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence hereto comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 24 and wherein the nucleic acid comprises a nucleic acid sequence, which is at least 90% identical to the nucleic acid sequence encoding the amino acid sequence as depicted in SEQ ID NO: 24; and other third phages comprise a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence hereto comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 25 and wherein the nucleic acid comprises a nucleic acid sequence, which is at least 90% identical to the nucleic acid sequence encoding the amino acid sequence as depicted in SEQ ID NO: 25. In a preferred embodiment, the present invention comprises a method of preparing a composition comprising isolated phages, the method comprising targeted isolating of phages comprised in a provided sample as defined herein, wherein i) the first phages comprise a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence hereto comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 1 and wherein the nucleic acid comprises a nucleic acid sequence, which is at least 95% identical to the nucleic acid sequence encoding the amino acid sequence as depicted in SEQ ID NO: 1 ; ii) the second phages comprise a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence hereto comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 11 and wherein the nucleic acid comprises a nucleic acid sequence, which is at least 95% identical to the nucleic acid sequence encoding the amino acid sequence as depicted in SEQ ID NO: 11 ; and other second phages comprise a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence hereto comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 12 and wherein the nucleic acid comprises a nucleic acid sequence, which is at least 95% identical to the nucleic acid sequence encoding the amino acid sequence as depicted in SEQ ID NO: 12; and iii) the third phages comprise a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence hereto comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 24 and wherein the nucleic acid comprises a nucleic acid sequence, which is at least 95% identical to the nucleic acid sequence encoding the amino acid sequence as depicted in SEQ ID NO: 24; and other third phages comprise a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence hereto comprising a nucleic acid sequence encoding an amino acid sequence as depicted in SEQ ID NO: 25 and wherein the nucleic acid comprises a nucleic acid sequence, which is at least 95% identical to the nucleic acid sequence encoding the amino acid sequence as depicted in SEQ ID NO: 25.

[00104] After the abovementioned targeted phage isolation, the isolated phages are obtained and provided within a composition as defined herein, meaning such isolated phages are then added to a pre-prepared composition as defined herein. The abovementioned can also be applied mutatis mutandis to a method of preparing a pharmaceutical composition as defined elsewhere herein.

[00105] Each definition made throughout the invention can also be applied, where necessary, to the method of preparing such (pharmaceutical) composition as well as to a composition comprising isolated phages obtainable or obtained by such method.

EXAMPLES OF THE INVENTION

[00106] Materials and Methods

[00107] Sample collection.

[00108] Sewage water was sampled regularly and kept at 4 °C before processing. The samples were used for isolating phages using classical isolation and viral tagging (VT).

[00109] Classical phage isolation.

[00110] The phages were amplified by mixing 50 ml of wastewater with the same amount of double-strength lysis buffer (LB) and 10 ml of a single Escherichia coli Reference collection (ECOR) strain bacteria cultured overnight. After incubation overnight at 30°C, 10 ml of the mixture was centrifuged at 6000xg at +4°C for 15 minutes and sterile filtered through a 0.45 pm membrane filter. Then, the phage titer was measured in plaque assays. Sterile filtered phage lysates were diluted in SM buffer or LB to five different dilutions (10e5 to 10e9). 100 pl of diluted phage and 200 pl of target bacteria (S. marcescens, K. pneumonia or P. aeruginosa) were mixed with 2 ml soft agar (SA), spread on pre-warmed LA plates, and incubated overnight at 30°C. The harvested phages were selected according to their plaque morphology.

[00111] VT experimental detail.

[00112] Viral stain and wash.

[00113] Dyes used to stain viruses, e.g. SYTO 9, SYBR Gold, SYBR Green II and SYBR Safe, were diluted to 50X in TE buffer (10 mM Tris, 1 mM EDTA; pH 8.0) for storage in -20°C in the dark until dilution to final concentration of 1- 5X for preparation of viral particles for VT (cf. Dzunkova et al. (Nature Microbiology (2019)) for labeling clinical samples). Viral samples were stained with dyes at 30 °C for 30 min for the environmental samples. The ultracentrifugal devices (100 KDa cut-off; Amicon) were pretreated by incubating 1.5 ml of 0.2pm-filter-sterilized 1 % BSA (Bioexpress, UT, cat# E531-1.5ML) in phosphate buffered saline (PBS) for 1 h at room temperature. Stained wastewater samples were washed six times by phage buffer in the pretreated ultracentrifugal devices. 50 pl phage buffer were added back for every 500 ml viral samples and sonicated (VWR Signature Ultrasonic cleaner B1500A-DTH, VWR) for 3 minutes using the settings of 50W at 42 kHz, resulted a 10-fold concentration of viruses from the original sample. Stained and washed viruses were mixed with bacteria (S. marcescens, K. pneumonia or P aeruginosa) at concentrations and ratios desired for flow cytometer analysis, typically 10⁵ cells per ml. VT experiments were done with a negative control, which was prepared identically to the stained and washed virus samples except without viruses; this controlled for free dye creating the appearance of false positive ‘viral tagged cells’.

[00114] The concentration of bacterial cells or viral particles to be combined in the VT assay was then adjusted by saline solution (SS, 0.9 % NaCI) to obtain a ratio of -100:1 to 1 :100 (bacteria to phage), where >1 .000 cells/sec were processed by FACS. Six 200 pl aliquots of the washed and diluted cell preparation were used as: 1) unstained bacterial cells mixed with SS, 2) stained bacterial cells mixed with SS, 3) unstained bacterial cells mixed with unstained virus-like particles (VLPs), 4) unstained bacterial cells mixed with stained VLPs. Bacterial cells for mixture 2 were stained with one microliter of dye, diluted 10X in sterile water, and incubated at room temperature in the dark for 30 min. Mixtures 1 to 3 were used as sorting controls and mixture 4 was the VT sample. All mixtures were incubated at 30 °C for 1 hour with mild rotary shaking to prevent sedimentation, and sample volumes were subsequently adjusted to 1 ml with SS before sorting using FACS. Non-specifically bound viruses were removed. [00115] Flow cytometry analyses and sorting.

[00116] Samples were examined using a FACSMelody™ (Becton Dickins Biosciences) or a MoFlo™ XDP (Beckman Coulter) cytometer. Fluorescence was detected using a 520/40 band pass filter with an amplified photomultiplier tube. Events were detected using a Forward Scatter trigger and data collected in logarithmic mode then analyzed with FlowJo™ v10 (Becton Dickins Biosciences) (Verity software house). Fluorescent polystyrene FLOW Check™ microspheres (1 m yellow-green beads; Polysciences Inc., PA, cat# 23517-10) were used as an internal standard. Samples were typically run with a concentration of 10⁵ cells ml¹.

[00117] The negative sorting controls were processed first in the following order: unstained bacterial cells, bacterial cells mixed with unstained VLPs, bacterial cells mixed with unstained viruses, and bacterial cells mixed with stained VLPs. The VT samples containing bacterial cells mixed with stained viruses were then processed, with 10,000 events usually recorded per sample to identify sorting gates which did not overlap with the negative controls. The final sample processed prior to sorting was the stained bacterial cell control to confirm that there was no overlap with the identified VT sorting gates. The flow cytometer was then cleaned prior to sorting of VT samples by repeatedly backflushing the fluidics and processing an ultra-pure water sample. For multi-cell sorts (50,000 or 100,000 cells), cells were collected in 1.5 ml low-bind tubes. For single-cell sorts, cells were sorted into 96 or 384 well plates with single-cell mode settings. The first, third and last column of the plate were left empty as negative controls, while 100 cells were collected into the second column as a positive amplification control. All sorted cells were stored at -80°C until further processing. Flow cytometry (.fsc) files were processed for visualisation using FlowViz and FlowCore R packages.

[00118] VT metagenomic sequencing.

[00119] Either VT or purified community viral samples were combined with 10 pl of DNAse I buffer and 5 pl of DNAse I (Sigma-Aldrich, #AMPD1-1 KT) and incubated for 15 min at room temperature to degrade free bacterial DNA in the viral filtrate. DNAse was inactivated by adding 10 pl DNAse stop solution and incubation at 70°C for 10 min. Viral DNA was then extracted using a low biomass DNA extraction method, which could also be applied to single cells (see below) (see, e.g., Dzunkova et al., loc cit. for viral DNA extraction). All reagents used in the DNA extraction were autoclaved, sterilized by 0.1 pm filtration and UV-radiated for 60 min. Each DNAsed virion sample (110 pl) was mixed with 77 pl of Lysis buffer prepared by combining 700 pl KOH stock (0.43g/10 ml), 430 pl DDT stock (Thermo Fisher, #R0861 , 0.8 g/10 ml) and 370 pl water, final pH 12. The sample was incubated for 10 min at room temperature, -80 °C for one hour and 55 °C for 5 min to complete virion lysis. The alkaline reaction was then neutralized by adding 77 pl of Stop buffer (5 g Tris-HCI in 10 ml, pH 4.5) and 1 pl of Proteinase K (20mg/ml, Sigma-Aldrich, #3115887001) was added to the sample and incubated for 30 min at 55 °C. The DNA was purified using 536 pl (1.8X sample volume) Agencourt AMPure beads (Beckman Coulter, #A63880) according to the manufacturer’s instructions. Each sample was finally resuspended in 30 pl of sterile water.

[00120] Purified viral DNAs were checked for contaminating prokaryotic or eukaryotic DNA by PCR amplification of 16S rRNA genes, 18S rRNA genes and human mitochondria positive controls used were E.coli and human gDNA diluted to 0.01 ng/pl and virion-free DNA extractions used as negative controls. An optimised protocol for ultra-low input samples (cf. Rinke et al., Peer J (2016), 4: e2486) was used to prepare libraries for sequencing on the NextSeq platform. Approximately 2 GB of 2 x 150 bp sequence data was obtained per sample.

[00121] Bioinformatics analysis.

[00122] Quality Control (QC).

[00123] Illumina data quality-control consisted of trimming ends with a quality score lower than 25 as well as sequences containing ambiguous bases, only reads longer than 100 bp were kept. Additionally, because the Illumina sequencing was done from linker-amplified DNA, it was mixed 1 :1 with phiX174 DNA to minimize base-calling issues in Illumina software. Thus full-length reads matching (>98% identity) to the phiX174 genome were removed and the remaining reads were considered the target material, linkers removed and quality controlled (cf. Deng et al., Nature (2014), 513: 242-245).

[00124] Assembly.

[00125] Contigs were assembled from post-QC reads using Velvet (Version 1.2.01) with a conservative k-mer size of 57 and the -cov cutoff option set to 10 as done previously (Hess et al., Science (2011), 331 : 463-467). Iterative assembly was used whereby reads incorporated into the largest contigs were removed in to compensate for highly variable coverage (30-500X) found across the genomes in these natural samples. After 15 rounds of assembly, 26 large contigs were obtained (> 30 kb that were ‘representative’ regions of the genome, see below) and referred as ‘Candidatus Genomes’. These 26 Candidatus Genomes utilized a total of -40% of the available reads; the remaining 60% of the data presumably belong to rare members of the phage community.

[00126] Protein clustering.

[00127] Open reading frames (ORFs) were predicted using prodigal (cf. Richards et al., Infect Genet Evol (2011), 11 : 1263-1275) from all contigs >1.5 Kb, including the CGs, as well as on all 454 reads that were not used in assembly. ORFs were clustered using CD-HIT (cf. Devirgilliis et al., Genes Nutr (2011), 6: 275-284) with a cutoff of 75% identity. Individual reads then were mapped to protein clusters using BLASTn, and evaluate a cutoff of 0.001 , only non-redundant top hits were used. Rarefaction curves were calculated using a custom perl script (Rarefaction.pl). Chao-1 index was calculated from the protein cluster data as described in Chao and Lee (J A Stat Assoc (1992), 87: 210-217). Simpson diversity index (D) (see Simpson, Nature (1949), 163: 688) was calculated as D= £n(n-1) I N(N-1). Shannon-Wiener (H’ = - p In p), was calculated using PHACCS (see above) (cf. Angly et al., BMC Bioinformatics (2005), 6: 41).

[00128] Contig annotation.

[00129] Assembled contigs >1.5 Kb were annotated as follows: ORFs were predicted using Prodigal (above) and functionally annotated using manually curated data resulting from BLASTp analyses against the non-redundant protein database of Genbank, and custom databases of T4 phage gene clusters (T4-GCs) (cf. Sullivan, Environ Microbiol (2010), 12: 3035-3056) and Microbial Metabolic Genes (cf. Sharon et al., ISME J (2011), 5: 1178-1190). To estimate the relative proportion of reads associated with particular viral types, a BLASTx search was used against the phage genomes available in NCBI, and assigned taxonomy to metagenomic reads by the taxon lineage associated with their top hit (requiring e-value < 1e-3), read2family.pl available was used with the rest of the scripts.

[00130] Hook designing.

[00131] The inventors used the genome of the isolated phages of S. marcescens, K. pneumoniae, and P. aeruginosa viral contigs generated by viral tagging, and the S. marcescens, K. pneumoniae, and P. aeruginosa phage genomes from the NCBI RefSeq database to create a gene catalogue. The proteins of these genes were clustered into protein families (PFs) using MMseqs2, and PFs were annotated using the PHROG database. In addition, phage genomes were clustered to genus level to create viral clusters (VCs) using vConTACT2. Then, a presenceabsence matrix (PAM) of PFs in VCs was created, and the most prevalent PFs and their functions were manually checked. The target PF was selected based on its prevalence in VCs and its function. For example, the inventors selected endolysin for designing the hooks for targeted isolation of phages as they were the most prevalent PF in VCs and had an important role in the bacteria lysing capacity of phages.

[00132] In vivo larvae work I.

[00133] The efficacy of phage therapy in vivo was assessed using the Galleria mellonella larval infection model. Larvae (250-300 mg) were infected with 10 pL of bacterial suspension (approximately 1 x 10⁶ CFU) of /? aeruginosa and K. pneumoniae (see Figure 7A and B) injected into the last left proleg. After 30 minutes, larvae were treated with 10 pL of the phage cocktail containing phages targeting Pseudomonas aeruginosa, Klebsiella pneumoniae, and Serratia marcescens (particularly the phage cocktail comprising HMGUsml , HMGUkpl , HMGUkp2, HMGUpa3 and HMGUpa4 as defined elsewhere herein), at multiplicity of infection (MOI) of 1 or 10. Control groups included bacteria only. Larvae were incubated at 37°C and monitored for survival over a 72-hour period. Death was defined as the absence of movement in response to touch, along with changes in color. Treatment efficacy was assessed by comparing survival rates among different groups.

[00134] In vitro assay.

[00135] To evaluate the inhibitory effect of the phage cocktail across multiple bacterial species, Pseudomonas aeruginosa (see Figure 8A) was grown in LB broth to mid-log phase and adjusted to an OD600 of 0.1. Cultures were treated with the phage cocktail containing phages targeting Pseudomonas aeruginosa, Klebsiella pneumoniae, and Serratia marcescens as defined herein (particularly the phage cocktail comprising HMGUsml , HMGUkpl , HMGUkp2, HMGUpa3 and HMGUpa4 as defined elsewhere herein), at a MOI of 1 for each component in combination with an antibiotic (Meropenem) in a concentration of 1 x minimum inhibition concentration (MIC) or 8 x MIC. Bacterial growth was monitored at 37°C in 96-well plates by measuring OD600 every 20 minutes for 48 hours using a microplate reader. Each treatment was performed in triplicate, and growth inhibition was compared across conditions. As a control, bacteria alone, phage cocktail alone, and antibiotic (Meropenem) in the abovementioned concentrations was used.

[00136] In vivo larvae work II.

[00137] The efficacy of phage therapy in vivo was assessed using the Galleria mellonella larval infection model. Larvae (250-300 mg) were infected with 10 pL of bacterial suspension (approximately 1 x 10⁶ CFU) of P. aeruginosa (see Figure 8B) injected into the last left proleg. After 30 minutes, larvae were treated with 10 pL of the phage cocktail containing phages targeting Pseudomonas aeruginosa, Klebsiella pneumoniae, and Serratia marcescens (particularly the cocktail comprising HMGUsml , HMGUkpl , HMGUkp2, HMGUpa3 and HMGUpa4 as defined elsewhere herein), at MOI of 1 with antibiotics in a concentration of 1 x MIC. Control groups included bacteria only, phage cocktail only, and antibiotic only treatments. Larvae were incubated at 37°C and monitored for survival over a 72-hour period. Death was defined as the absence of movement in response to touch, along with changes in color. Treatment efficacy was assessed by comparing survival rates among different groups.

[00138] Results.

[00139] Example 1.

[00140] The inventors used in-depth comparative genomics and protein clustering to build a presence-absence matrix (see Figure 1) of protein families shared between the viral clusters from the viral-tagging (Deng et al., 2014; Dzunkova et al., 2019) data generated against Serratia marcescens, Klebsiella pneumoniae, and Pseudomonas aeruginosa, also Serratia, Klebsiella, and Pseudomonas phages from the NCBI RefSeq database were included. The inventors identified multiple proteins shared between these viral clusters (see Figure 1). Protein clusters from those genes that showed the highest similarities between viral clusters were selected (see Figure 1) as markers for developing a targeted isolation approach, which can be used to isolate novel phages from the environment and clinical samples with high antibacterial effects (see Table 1).

Table 1 : Amino acid sequences of SEQ ID NOs 1-44.

[00141] Example 2.

[00142] The inventors evaluated the efficacy of isolated phages against their target bacteria, such as S. marcescens (see Figure 2A-C), K. pneumoniae (see Figure 3A and B), and P. aeruginosa (see Figure 4A and B). The inventors then further characterized their morphological features (see Figure 5A-C). All tested phages showed high efficacy against their target bacteria.

[00143] Example 3.

[00144] The inventors evaluated the efficacy of a combination of five phages (phage cocktail), namely HMGUsml , HMGUkpl, HMGUkp2, HMGUpa3 and HMGUpa4 against three target bacteria: S. marcescens, K. pneumoniae, and P. aeruginosa (see Figure 6A-C). The combination showed high efficacy against these bacteria (see Figure 6A-C). ITEMS A composition comprising: a) isolated first phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence hereto comprising a nucleic acid sequence encoding an amino acid sequence as depicted in at least any one selected from the group consisting of SEQ ID NOs: 1-10, wherein the phages are capable of suppressing growth of Serratia marcescens such that OD600 is not higher than 0.5; b) isolated second phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence hereto comprising a nucleic acid sequence encoding an amino acid sequence as depicted in at least any one selected from the group consisting of SEQ ID NOs: 11-23, wherein the phages are capable of suppressing growth of Klebsiella pneumoniae such that QD600 is not higher than 0.5; and c) isolated third phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence hereto comprising a nucleic acid sequence encoding an amino acid sequence as depicted in at least any one selected from the group consisting of SEQ ID NOs: 24-44, wherein the phages are capable of suppressing growth of Pseudomonas aeruginosa such that QD600 is not higher than 0.5. The composition of item 1 , wherein i) said first phages are capable of suppressing growth of Serratia marcescens such that QD600 is not higher than 0.2; ii) said second phages are capable of suppressing growth of Klebsiella pneumoniae such that QD600 is not higher than 0.2, and iii) said third phages are capable of suppressing growth of Pseudomonas aeruginosa such that QD600 is not higher than 0.2. The composition of item 1 or 2, wherein said composition has bactericidal activity against at least any one of Serratia marcescens, Klebsiella pneumoniae, or Pseudomonas aeruginosa. The composition of any one of items 1-3, wherein the Serratia marcescens bacteria, the Klebsiella pneumoniae bacteria, and the Pseudomonas aeruginosa bacteria are antimicrobial resistance (AMR) bacteria. The composition of any one of the preceding items, further comprising a buffer. The composition of any one of the preceding items, wherein i) the first phages comprise a nucleic acid being part of their genome, wherein the nucleic acid comprises a nucleic acid sequence, which is at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, at least 98%, at least 99% or 100% identical to the nucleic acid sequence encoding the amino acid sequence as depicted in at least any one selected from the group consisting of SEQ ID NOs: 1-10; ii) the second phages comprise a nucleic acid being part of their genome, wherein the nucleic acid comprises a nucleic acid sequence, which is at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, at least 98%, at least 99% or 100% identical to the nucleic acid sequence encoding the amino acid sequence as depicted in at least any one selected from the group consisting of SEQ ID NOs: 11-23; and iii) the third phages comprise a nucleic acid being part of their genome, wherein the nucleic acid comprises a nucleic acid sequence, which is at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, at least 98%, at least 99% or 100% identical to the nucleic acid sequence encoding the amino acid sequence as depicted in at least any one selected from the group consisting of SEQ ID NOs: 24-44. A pharmaceutical composition comprising the composition of any one of the preceding items. The composition of any one of items 1-6 or the pharmaceutical composition of item 7 for use in therapy. The composition of any one of items 1-6 or the pharmaceutical composition of item 7 for use in a method of treating or preventing a bacterial infection caused by at least any one of Pseudomonas aeruginosa, Klebsiella pneumoniae or Serratia marcescens in a subject, preferably wherein the subject also suffers from an infection with SARS-CoV-2. A kit comprising the composition of any one of items 1 -6 or the pharmaceutical composition of item 7. A kit comprising i) a first nucleic acid sequence, which is at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, at least 98%, at least 99% or 100% identical to a nucleic acid sequence encoding an amino acid sequence as depicted in at least any one selected from the group consisting of SEQ ID NOs: 1-10, or a complementary sequence thereof; ii) a second nucleic acid sequence, which is at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, at least 98%, at least 99% or 100% identical to a nucleic acid sequence encoding an amino acid sequence as depicted in at least any one selected from the group consisting of SEQ ID NOs: 11-23, or a complementary sequence thereof; and iii) a third nucleic acid sequence, which is at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, at least 98%, at least 99% or 100% identical to a nucleic acid sequence encoding an amino acid sequence as depicted in at least any one selected from the group consisting of SEQ ID NOs: 24-44, or a complementary sequence thereof. The kit of item 11 , wherein each of the nucleic acid sequences are conjugated to a detectable label. A method of preparing a composition comprising isolated phages, the method comprising: targeted isolating of phages comprised in a provided sample, wherein i) the first phages comprise a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence hereto comprising a nucleic acid sequence encoding an amino acid sequence as depicted in at least any one selected from the group consisting of SEQ ID NOs: 1-10 and wherein the nucleic acid comprises a nucleic acid sequence, which is at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, at least 98%, at least 99% or 100% identical to the nucleic acid sequence encoding the amino acid sequence as depicted in at least any one selected from the group consisting of SEQ ID NOs: 1-10; ii) the second phages comprise a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence hereto comprising a nucleic acid sequence encoding an amino acid sequence as depicted in at least any one selected from the group consisting of SEQ ID NOs: 11-23 and wherein the nucleic acid comprises a nucleic acid sequence, which is at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, at least 98%, at least 99% or 100% identical to the nucleic acid sequence encoding the amino acid sequence as depicted in at least any one selected from the group consisting of SEQ ID NOs: 11-23; and iii) the third phages comprise a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence hereto comprising a nucleic acid sequence encoding an amino acid sequence as depicted in at least any one selected from the group consisting of SEQ ID NOs: 24-44 and wherein the nucleic acid comprises a nucleic acid sequence, which is at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, at least 98%, at least 99% or 100% identical to the nucleic acid sequence encoding the amino acid sequence as depicted in at least any one selected from the group consisting of SEQ ID NOs: 24-44. The method of item 13, wherein the sample is any one of a naturally environmental sample, a clinical sample, a wastewater treatment plant sample, or a hospital waste resources sample. composition comprising isolated phages obtainable or obtained by the method of any one of items 13-14.

Claims

1 . A composition comprising: a) isolated first phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence hereto comprising a nucleic acid sequence encoding an amino acid sequence as depicted in at least any one selected from the group consisting of SEQ ID NOs: 1-10, wherein the phages are capable of suppressing growth of Serratia marcescens such that OD600 is not higher than 0.5, and wherein said nucleic acid being part of their genome comprises a nucleic acid sequence, which is at least 80% identical to the nucleic acid sequence encoding the amino acid sequence as depicted in at least any one selected from the group consisting of SEQ ID NOs: 1-10; b) isolated second phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence hereto comprising a nucleic acid sequence encoding an amino acid sequence as depicted in at least any one selected from the group consisting of SEQ ID NOs: 11-23, wherein the phages are capable of suppressing growth of Klebsiella pneumoniae such that QD600 is not higher than 0.5, and wherein said nucleic acid being part of their genome comprises a nucleic acid sequence, which is at least 80% identical to the nucleic acid sequence encoding the amino acid sequence as depicted in at least any one selected from the group consisting of SEQ ID NOs: 11-23; and c) isolated third phages comprising a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence hereto comprising a nucleic acid sequence encoding an amino acid sequence as depicted in at least any one selected from the group consisting of SEQ ID NOs: 24-44, wherein the phages are capable of suppressing growth of Pseudomonas aeruginosa such that QD600 is not higher than 0.5, and wherein said nucleic acid being part of their genome comprises a nucleic acid sequence, which is at least 80% identical to the nucleic acid sequence encoding the amino acid sequence as depicted in at least any one selected from the group consisting of SEQ ID NOs: 24-44.

2. The composition of claim 1 , wherein i) said first phages are capable of suppressing growth of Serratia marcescens such that OD600 is not higher than 0.2; ii) said second phages are capable of suppressing growth of Klebsiella pneumoniae such that OD600 is not higher than 0.2, and iii) said third phages are capable of suppressing growth of Pseudomonas aeruginosa such that OD600 is not higher than 0.2.

3. The composition of claim 1 or 2, wherein said composition has bactericidal activity against at least any one of Serratia marcescens, Klebsiella pneumoniae, or Pseudomonas aeruginosa.

4. The composition of any one of claims 1-3, wherein the Serratia marcescens bacteria, the Klebsiella pneumoniae bacteria, and the Pseudomonas aeruginosa bacteria are antimicrobial resistance (AMR) bacteria.

5. The composition of any one of the preceding claims, further comprising a buffer.

6. The composition of any one of the preceding claims, wherein i) the first phages comprise a nucleic acid being part of their genome, wherein the nucleic acid comprises a nucleic acid sequence, which is at least 90%, at least 95%, at least 98%, at least 99% or 100% identical to the nucleic acid sequence encoding the amino acid sequence as depicted in at least any one selected from the group consisting of SEQ ID NOs: 1-10; ii) the second phages comprise a nucleic acid being part of their genome, wherein the nucleic acid comprises a nucleic acid sequence, which is at least 90%, at least 95%, at least 98%, at least 99% or 100% identical to the nucleic acid sequence encoding the amino acid sequence as depicted in at least any one selected from the group consisting of SEQ ID NOs: 11-23; and iii) the third phages comprise a nucleic acid being part of their genome, wherein the nucleic acid comprises a nucleic acid sequence, which is at least 90%, at least 95%, at least 98%, at least 99% or 100% identical to the nucleic acid sequence encoding the amino acid sequence as depicted in at least any one selected from the group consisting of SEQ ID NOs: 24-44.

7. A pharmaceutical composition comprising the composition of any one of the preceding claims.

8. The pharmaceutical composition of claim 7, which is administered in combination with an antibiotic.

9. The pharmaceutical composition of claim 8, wherein the antibiotic is a carbapenem, preferably Meropenem.

10. The composition of any one of claims 1-6 or the pharmaceutical composition of any one of claims 7-9 for use in therapy.

11. The composition of any one of claims 1-6 or the pharmaceutical composition of any one of claims 7-9 for use in a method of treating or preventing a bacterial infection caused by at least any one of Pseudomonas aeruginosa, Klebsiella pneumoniae or Serratia marcescens in a subject, preferably wherein the subject also suffers from an infection with SARS-CoV-2.

12. A kit comprising the composition of any one of claims 1-6 or the pharmaceutical composition of any one of claims 7-9.

13. A kit comprising i) a first nucleic acid sequence, which is at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, at least 98%, at least 99% or 100% identical to a nucleic acid sequence encoding an amino acid sequence as depicted in at least any one selected from the group consisting of SEQ ID NOs: 1-10, or a complementary sequence thereof; ii) a second nucleic acid sequence, which is at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, at least 98%, at least 99% or 100% identical to a nucleic acid sequence encoding an amino acid sequence as depicted in at least any one selected from the group consisting of SEQ ID NOs: 11-23, or a complementary sequence thereof; and iii) a third nucleic acid sequence, which is at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, at least 98%, at least 99% or 100% identical to a nucleic acid sequence encoding an amino acid sequence as depicted in at least any one selected from the group consisting of SEQ ID NOs: 24-44, or a complementary sequence thereof.

14. The kit of claim 13, wherein each of the nucleic acid sequences are conjugated to a detectable label.

15. A method of preparing a composition comprising isolated phages, the method comprising: targeted isolating of phages comprised in a provided sample, wherein i) the first phages comprise a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence hereto comprising a nucleic acid sequence encoding an amino acid sequence as depicted in at least any one selected from the group consisting of SEQ ID NOs: 1-10 and wherein the nucleic acid comprises a nucleic acid sequence, which is at least 80%, at least 90%, at least 95%, at least 98%, at least 99% or 100% identical to the nucleic acid sequence encoding the amino acid sequence as depicted in at least any one selected from the group consisting of SEQ ID NOs: 1-10; ii) the second phages comprise a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence hereto comprising a nucleic acid sequence encoding an amino acid sequence as depicted in at least any one selected from the group consisting of SEQ ID NOs: 11-23 and wherein the nucleic acid comprises a nucleic acid sequence, which is at least 80%, at least 90%, at least 95%, at least 98%, at least 99% or 100% identical to the nucleic acid sequence encoding the amino acid sequence as depicted in at least any one selected from the group consisting of SEQ ID NOs: 11-23; and iii) the third phages comprise a nucleic acid being part of their genome, which hybridizes under stringent conditions to a signature sequence or its complementary sequence hereto comprising a nucleic acid sequence encoding an amino acid sequence as depicted in at least any one selected from the group consisting of SEQ ID NOs: 24-44 and wherein the nucleic acid comprises a nucleic acid sequence, which is at least 80%, at least 90%, at least 95%, at least 98%, at least 99% or 100% identical to the nucleic acid sequence encoding the amino acid sequence as depicted in at least any one selected from the group consisting of SEQ ID NOs: 24-44.

16. The method of claim 15, wherein the sample is any one of a naturally environmental sample, a clinical sample, a wastewater treatment plant sample, or a hospital waste resources sample.

17. A composition comprising isolated phages obtainable or obtained by the method of any one of claims 15-16.