Frontiers in Microbiology (Feb 2020)
Coexistence of Two blaNDM–5 Genes Carried on IncX3 and IncFII Plasmids in an Escherichia coli Isolate Revealed by Illumina and Nanopore Sequencing
Abstract
The emergence of carbapenem-resistant Enterobacteriaceae poses a significant threat to public health worldwide. Here, we reported a multidrug-resistant Escherichia coli strain with two different blaNDM–5-carrying plasmids from China. Illumina short-read and MinION long-read whole genome sequencing were performed. Genomic analysis found that one blaNDM–5 gene together with mphA was located on a 55-kb IncX3 plasmid, while the other blaNDM–5 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 blaNDM–5 than those with both plasmids or the IncFII plasmid. Two other β-lactamase genes (blaCTX–M–15 and blaOXA–1) were also detected on another 160-kb IncF plasmid. This is the first report of coexistence of two blaNDM–5-carrying plasmids in a single bacterial isolate, highlighting the genetic complexity of NDM-5 carbapenemase circulation, and the urgent need for continued active surveillance.
Keywords
