Co-conjugation of Virulence Plasmid and KPC Plasmid in a Clinical Klebsiella pneumoniae Strain

Abstract

Carbapenem-resistant hypervirulent <i>Klebsiella pneumoniae</i> (CR-HvKP) strains have been increasingly reported, and it is important to understand the evolutionary mechanisms of these highly pathogenic and resistant bacterial pathogens. In this study, we characterized a ST11 carbapenem-resistant <i>K. pneumoniae</i> strain which harbored an IncFIB/IncHI1B type virulence plasmid and an IncFII/IncR type <i>bla</i> _<i>KPC</i> _- ₂-bearing plasmid. The virulence plasmid was found to be conjugative and harbored a 35-kbp fragment including aerobactin encoding cluster from virulence plasmid pLVPK and multiple resistance genes, resulting in a mosaic multi-drug resistance and virulence plasmid. This virulence plasmid could be transferred via conjugation to <i>Escherichia coli</i> and <i>K. pneumoniae</i> strains alone as well as together with the <i>bla</i> _<i>KPC</i> _- ₂-bearing plasmid. Co-transmission of virulence and <i>bla</i> _<i>KPC</i> _- ₂-bearing plasmids would directly convert a classic <i>K. pneumoniae</i> strain into CR-HvKP strain, leading to a sharp increase in the prevalence of CR-HvKP in clinical settings, which poses a great threat to human health.