Isolation, characterization, and genomic analysis of phage MY02 targeting extended-spectrum beta-lactamase-producing Klebsiella pneumoniae.

Abuse of antibiotics has led to increased rates of resistance in extended-spectrum beta-lactamase (ESBL)-producing Klebsiella pneumoniae and an acceleration in the emergence of drug-resistant strains, which can have serious consequences for nosocomial infections. In this study, phage MY02, which infects ESBL-producing Klebsiella pneumoniae, was isolated from sewage and characterized. Phage MY02 was found to have an optimal multiplicity of infection of 0.001, with a lysis period of up to 40 minutes and an average burst of about 80 plaque-forming units per cell. The phage was found to be stable over a temperature range of -20 to 60°C and a pH range of 3-11 and to have a broad host range. Whole-genome sequencing showed that the genome of phage MY02 is ??171,821?? bp in length and contains 293 open reading frames. Sequence comparisons and phylogenetic analysis showed that phage MY02 belongs to the genus Marfavirus in the class Caudoviricetes. This novel broad-spectrum Klebsiella pneumoniae phage has potential applications against bacterial infections.