Colocation of the Polymyxin Resistance Gene mcr-1 and a Variant of mcr-3 on a Plasmid in an Escherichia coli Isolate from a Chicken Farm

Antimicrob Agents Chemother. 2018 May 25;62(6):e00501-18. doi: 10.1128/AAC.00501-18. Print 2018 Jun.

Abstract

A colistin-resistant Escherichia coli isolate from a commercial poultry farm in China carried two colistin resistance genes, mcr-1 and variant of mcr-3, in an IncP plasmid. The variant of the mcr-3 gene, named mcr-3.11, encoded two amino acid substitutions compared with the mcr-3 gene. A novel genetic structure, ISKpn40-mcr-3-dgkA-ISKpn40, might be the key element mediating the translocation of mcr-3 through the formation of a circular form. The mcr-1 and mcr-3 genes, which are colocated on a plasmid, might pose a huge threat to public health.

Keywords: Escherichia coli; circular form; colistin; mcr-1; mcr-3.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Anti-Bacterial Agents
  • Chickens
  • Colistin / pharmacology*
  • Drug Resistance, Bacterial
  • Escherichia coli / drug effects*
  • Escherichia coli / genetics
  • Escherichia coli / metabolism*
  • Escherichia coli Proteins / genetics
  • Escherichia coli Proteins / metabolism*
  • Farms
  • Microbial Sensitivity Tests
  • Plasmids / genetics*
  • Polymyxins / pharmacology*
  • Transferases (Other Substituted Phosphate Groups) / genetics
  • Transferases (Other Substituted Phosphate Groups) / metabolism

Substances

  • Anti-Bacterial Agents
  • Escherichia coli Proteins
  • MCR-1 protein, E coli
  • Polymyxins
  • MCR-3 protein, E coli
  • Transferases (Other Substituted Phosphate Groups)
  • Colistin