ISOLATION AND CHARACTERIZATION OF PHAGES AGAINST PAN-RESISTANT KLEBSIELLA PNEUMONIAE

PUJATO SILVINA ALICIA; MERCANTI, DIEGO; QUIBERONI ANDREA; NATALIA PUJATO; MARCELO RADISIC; MARCÓ, MARIÁNGELES BRIGGILER

Congreso; 32 CONGRESO BRASILERO DE MICROBIOLOGÍA; 2023

Antibiotic resistance is a growing public health challenge worldwide. In particular, infectionscaused by the bacterium Klebsiella pneumoniae have become increasingly difficult to treat dueto their ability to develop resistance to multiple antibiotics. In September 2022, acarbapenemase-producing strain of Klebsiella pneumoniae was isolated in Argentina. Whendetermining the Minimum Inhibitory Concentration (MIC) and/or the disk diffusion test,phenotypic resistance to penicillins, cephalosporins, monobactams, carbapenems,aminoglycosides, fosfomycin, lipopeptides, tetracyclines/glycylcyclines, quinolones, rifamycins,folate inhibitors, phenicols, and nitrofurans available in Argentina was confirmed. Due to its highresistance, the use of bacteriophages was considered as an alternative for its treatment.The objective of this study was to isolate, characterize, and sequence bacteriophages capable oflysing antibiotic-resistant strains of Klebsiella pneumoniae and to select those that do notpossess antibiotic resistance genes or lysogeny-associated genes for use in phage therapy.Wastewater samples from meat locker and sewage near a hospital were collected to isolateKlebsiella pneumoniae bacteriophages. Phages were propagated in LB-Ca-Mg broth. DNA wasextracted with phenol-chloroform, and its restriction pattern was analyzed using BioNumerics™V6 software. DNA sequencing was performed with the DNA Nextera XT kit (Illumina). Sequenceswere assembled and quality assessed using FastQ software. Genome assembly was confirmedby PCR, and genes were predicted using GeneMark and ORF Finder. Sequences were comparedto other phage genomes using NCBI blast.It was possible to isolate a total of 8 highly specific phages for the pan-resistant strain ofKlebsiella pneumoniae. All demonstrated the ability to lyse the strain in a liquid medium in 3hours, obtaining a titer of 1010 PFU/mL. When cut with enzymes, 5 different patterns wereobserved. The sequencing analysis revealed that the selected phages did not have antibioticresistance genes or genes associated with lysogeny.The results obtained indicate that the specific bacteriophages isolated in this study could be apromising alternative as adjuvants to antibiotic therapy in the treatment of infections caused bythe antibiotic-resistant strain of Klebsiella pneumoniae. The ability of phages to selectively killtarget bacteria, without affecting healthy human cells, and their ability to adapt to constantlyevolving bacteria make them a potentially effective option against resistant strains.