Identification of a Novel Hybrid Plasmid Encoding KPC-2 and Virulence Factors in Klebsiella pneumoniae Sequence Type 11.

Recent emergence of carbapenem-resistant Klebsiella pneumoniae (CRKP) coharboring bla KPC-2 and pLVPK-like virulence plasmids represented a novel clinical challenge. In the present study, we characterized a bla KPC-2 and virulence hybrid plasmid, designated pCRHV-C2244, from a clinical ST11-K64 CRKP strain. pCRHV-C2244 was non-self-transmissible due to incomplete conjugative elements but mobilizable together with a conjugative helper. Enhanced virulence and stable maintenance without significant fitness loss in its original host were confirmed in vitro and in vivo.