Characterization and Functional Studies of a Novel Depolymerase Against K19-Type .

Carbapenem-resistant (CRKP), a pathogen that causes severe nosocomial infections and yields a high mortality rate, poses a serious threat to global public health due to its high antimicrobial resistance. Bacteriophages encode polysaccharide-degrading enzymes referred to as depolymerases that cleave the capsular polysaccharide (CPS), one of the main virulence factors of . In this study, we identified and characterized a new capsule depolymerase K19-Dpo41 from bacteriophage SH-KP156570. Our characterization of K19-Dpo41 demonstrated that this depolymerase showed specific activities against K19-type . K19-Dpo41-mediated treatments promoted the sensitivity of a multidrug-resistant K19-type strain to the bactericidal effect of human serum and significantly increased the survival rate of infected with K19-type . Our results provided strong primary evidence that K19-Dpo41 was not only effective in capsular typing of K19-type but promising in terms of developing new alternative therapeutic strategies against K19-type CRKP infections in the future.