Identification and characterization of the first Escherichia coli strain carrying NDM-1 gene in China

PLoS One. 2013 Jun 10;8(6):e66666. doi: 10.1371/journal.pone.0066666. Print 2013.

Abstract

New Delhi metallo-β-lactamase-1 (NDM-1), an acquired class B carbapenemase, is a significant clinical threat due to its extended hydrolysis of β-lactams including carbapenems. In this study, we identified the first confirmed clinical isolate of Escherichia coli BJ01 harboring bla(NDM-1) in China. The isolate is highly resistant to all tested antimicrobials except polymyxin. bla(NDM-1), bla(CTX-M-57), and bla TEM-1 were identified in the isolate. bla(NDM-1) was transferable to E. coli EC600 and DH5α in both plasmid conjugation experiments and plasmid transformation tests. BJ01 was identified as a new sequence type, ST224, by multilocus sequence typing. Analysis of genetic environment shows complex transposon-like structures surrounding the bla NDM-1 gene. Genetic analysis revealed that the region flanking bla(NDM-1) was very similar to previously identified NDM-positive Acinetobacter spp. isolated in China. The findings of this study raise attention to the emergence and spread of NDM-1-carrying Enterobacteriaceae in China.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • Blotting, Southern
  • Carbapenems / pharmacology*
  • China
  • Conjugation, Genetic
  • DNA, Bacterial / genetics
  • Drug Resistance, Multiple, Bacterial / genetics*
  • Escherichia coli / drug effects
  • Escherichia coli / genetics
  • Escherichia coli / isolation & purification*
  • Escherichia coli Infections / drug therapy
  • Escherichia coli Infections / epidemiology
  • Escherichia coli Infections / microbiology*
  • Humans
  • Microbial Sensitivity Tests
  • Multilocus Sequence Typing
  • Plasmids / genetics
  • Polymerase Chain Reaction
  • Transformation, Bacterial
  • beta-Lactamases / genetics
  • beta-Lactamases / metabolism*

Substances

  • Carbapenems
  • DNA, Bacterial
  • beta-Lactamases
  • beta-lactamase NDM-1

Grants and funding

This work was supported by Internal Funding of Guang'anmen Hospital (Grant# 2011S242) and Beijing You'an Project for Liver diseases and AIDS (Grant# JYAN-2011-064). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.