Coexistence of Two Genes Carried on IncX3 and IncFII Plasmids in an Isolate Revealed by Illumina and Nanopore Sequencing.

The emergence of carbapenem-resistant poses a significant threat to public health worldwide. Here, we reported a multidrug-resistant strain with two different -carrying plasmids from China. Illumina short-read and MinION long-read whole genome sequencing were performed. Genomic analysis found that one gene together with was located on a 55-kb IncX3 plasmid, while the other gene was on a novel 68-kb IncFII plasmid. Susceptibility testing and quantitative reverse transcription PCR results further indicated that the transconjugants with the IncX3 plasmid exhibited higher-level carbapenem resistance and expression of than those with both plasmids or the IncFII plasmid. Two other β-lactamase genes ( and ) were also detected on another 160-kb IncF plasmid. This is the first report of coexistence of two -carrying plasmids in a single bacterial isolate, highlighting the genetic complexity of NDM-5 carbapenemase circulation, and the urgent need for continued active surveillance.