Characterization of a Conjugative Hybrid Plasmid Coharboring <i>bla</i> _KPC-2 and <i>bla</i> _IMP-4 in a Klebsiella quasipneumoniae Clinical Isolate

Abstract

strains. Our study described the cooccurrence of KPC-2, a serine β-lactamase, and IMP-4, a metallo-β-lactamase (MBL), on a conjugative hybrid plasmid from a clinical carbapenem-resistant K. quasipneumoniae strain, and it revealed an alternative route for IncHI5 plasmid to evolve by recombining with other plasmids to form a hybrid plasmid. Moreover, this hybrid plasmid can be transferred into other Klebsiella species and stably persist during passage. The propagation of two important carbapenemase genes with a new genetic background using well-evolved plasmids in the clinical setting promotes the emergence of superbugs that require careful monitoring.