Genetic characterization of blaNDM-harboring plasmids in carbapenem-resistant Escherichia coli from Myanmar

PLoS One. 2017 Sep 14;12(9):e0184720. doi: 10.1371/journal.pone.0184720. eCollection 2017.

Abstract

The bacterial enzyme New Delhi metallo-β-lactamase hydrolyzes almost all β-lactam antibiotics, including carbapenems, which are drugs of last resort for severe bacterial infections. The spread of carbapenem-resistant Enterobacteriaceae that carry the New Delhi metallo-β-lactamase gene, blaNDM, poses a serious threat to public health. In this study, we genetically characterized eight carbapenem-resistant Escherichia coli isolates from a tertiary care hospital in Yangon, Myanmar. The eight isolates belonged to five multilocus-sequence types and harbored multiple antimicrobial-resistance genes, resulting in resistance against nearly all of the antimicrobial agents tested, except colistin and fosfomycin. Nine plasmids harboring blaNDM genes were identified from these isolates. Multiple blaNDM genes were found in the distinct Inc-replicon types of the following plasmids: an IncA/C2 plasmid harboring blaNDM-1 (n = 1), IncX3 plasmids harboring blaNDM-4 (n = 2) or blaNDM-7 (n = 1), IncFII plasmids harboring blaNDM-4 (n = 1) or blaNDM-5 (n = 3), and a multireplicon F plasmid harboring blaNDM-5 (n = 1). Comparative analysis highlighted the diversity of the blaNDM-harboring plasmids and their distinct characteristics, which depended on plasmid replicon types. The results indicate circulation of phylogenetically distinct strains of carbapenem-resistant E. coli with various plasmids harboring blaNDM genes in the hospital.

Publication types

  • Comparative Study

MeSH terms

  • Carbapenems / pharmacology
  • DNA, Bacterial / genetics
  • Escherichia coli / classification*
  • Escherichia coli / genetics
  • Escherichia coli / isolation & purification
  • Escherichia coli Infections / microbiology*
  • Escherichia coli Proteins / genetics
  • Evolution, Molecular
  • Humans
  • Microbial Sensitivity Tests
  • Multilocus Sequence Typing
  • Myanmar
  • Phylogeny
  • Plasmids / genetics*
  • Sequence Analysis, DNA / methods
  • beta-Lactam Resistance*
  • beta-Lactamases / genetics*

Substances

  • Carbapenems
  • DNA, Bacterial
  • Escherichia coli Proteins
  • beta-Lactamases
  • beta-lactamase NDM-1

Grants and funding

This study was supported by the Japan Initiative for Global Research Network on Infectious Diseases (J-GRID) from Ministry of Education, Culture, Sport, Science and Technology in Japan (MEXT), and Japan Agency for Medical Research and Development (AMED, URL: http://www.amed.go.jp/en/). The funder had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.