Identification of one plasmid harboring tmexCD1-toprJ1 in clinical Klebsiella pneumoniae

Two clinical K. pneumoniae strains coharboring carbapenemase genes and novel tmexCD1-toprJ1 RND efflux pump were characterized here. The novel RND efflux pump gene cluster tmexCD1-toprJ1 coexisted with blaNDM-1 or blaKPC-2 in IncHI5-like and IncFII conjugative plasmids. This study highlights the emerging convergence of carbapenemase genes and tmexCD1-toprJ1 in typical MDR plasmids among clinical K. pneumoniae, which threatens treatments of CRKP infections. Epidemiology of such pathogens is warranted intensive investigations to evaluate the public health risk.