New Variant of mcr-3 in an Extensively Drug-Resistant Escherichia coli Clinical Isolate Carrying mcr-1 and blaNDM-5

Antimicrob Agents Chemother. 2017 Nov 22;61(12):e01757-17. doi: 10.1128/AAC.01757-17. Print 2017 Dec.

Abstract

A colistin- and carbapenem-resistant Escherichia coli clinical isolate was found to carry two plasmid-borne colistin-resistant genes, mcr-1 and the newly identified mcr-3, and a carbapenemase gene, blaNDM-5mcr-3 is a new variant (mcr-3.5) in the isolate and encodes three amino acid substitutions compared with the original MCR-3. mcr-3 was carried by a TnAs3-like transposon on a self-transmissible IncP plasmid in the isolate, highlighting that mcr-3 may have widely spread.

Keywords: Enterobacteriaceae; Escherichia coli; colistin; plasmids; resistance.

MeSH terms

  • Amino Acid Substitution
  • Anti-Bacterial Agents / pharmacology
  • Colistin / pharmacology
  • DNA Transposable Elements
  • Drug Resistance, Multiple, Bacterial / genetics*
  • Escherichia coli / drug effects
  • Escherichia coli / enzymology
  • Escherichia coli / genetics*
  • Escherichia coli / isolation & purification
  • Escherichia coli Infections / microbiology
  • Escherichia coli Proteins / genetics*
  • Escherichia coli Proteins / metabolism
  • Gene Expression Regulation, Bacterial*
  • Humans
  • Microbial Sensitivity Tests
  • Mutation
  • Plasmids / chemistry
  • Plasmids / metabolism
  • Protein Isoforms / genetics
  • Protein Isoforms / metabolism
  • beta-Lactamases / genetics*
  • beta-Lactamases / metabolism

Substances

  • Anti-Bacterial Agents
  • DNA Transposable Elements
  • Escherichia coli Proteins
  • MCR-1 protein, E coli
  • Protein Isoforms
  • beta lactamase NDM-5, E coli
  • beta-Lactamases
  • Colistin