Molecular Epidemiology of Carbapenemase-Producing Escherichia Coli and the Prevalence of ST131 Subclone H30 in Shanghai, China

Eur J Clin Microbiol Infect Dis. 2015 Jun;34(6):1263-9. doi: 10.1007/s10096-015-2356-3. Epub 2015 Mar 11.

Abstract

The molecular characteristics and epidemiology of carbapenemase-producing Escherichia coli (CPEC) isolates from Shanghai, China, were investigated using 21 imipenem-resistant E. coli isolates obtained from a Shanghai teaching hospital from 2011 to 2014. The presence of bla KPC, bla IMP, bla VIM, bla OXA-48, and bla NDM was assessed by polymerase chain reaction (PCR) amplification and sequencing. CPEC isolates were characterized by the Etest®, multilocus sequence typing (MLST), and pulse-field gel electrophoresis (PFGE). Plasmids carrying resistance genes were analyzed by conjugation experiments, replicon typing, plasmid MLST (pMLST), S1 nuclease PFGE (S1-PFGE), and Southern hybridization. The genetic environment of the resistance genes was determined by PCR and sequencing. Among the 21 E. coli isolates, 16 produced carbapenemases; of these, ten isolates transferred carbapenemase-encoding plasmids to recipient bacteria. Nine of the 16 isolates were clonally related, and their PFGE patterns were designated type A. ST131 was the predominant sequence type (11 isolates, 68.8 %); the H30 subclone comprised 81.8 % of the ST131 strains. In all three isolates, bla IMP-4 was located on 50-kb IncN plasmids. All but two bla KPC-2 genes were carried on IncF plasmids of various sizes. Hence, both clone-spread and horizontal transfer mediated the dissemination of carbapenemase-producing genes in the Shanghai isolates.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Bacterial Proteins / genetics
  • Bacterial Proteins / metabolism*
  • Blotting, Southern
  • China / epidemiology
  • Cluster Analysis
  • DNA, Bacterial / genetics
  • Disk Diffusion Antimicrobial Tests
  • Escherichia coli / classification*
  • Escherichia coli / enzymology*
  • Escherichia coli / genetics
  • Escherichia coli / isolation & purification
  • Escherichia coli Infections / epidemiology*
  • Escherichia coli Infections / microbiology*
  • Genotype
  • Hospitals, Teaching
  • Humans
  • Molecular Epidemiology
  • Molecular Typing
  • Plasmids / analysis
  • Polymerase Chain Reaction
  • Prevalence
  • Sequence Analysis, DNA
  • beta-Lactamases / genetics
  • beta-Lactamases / metabolism*

Substances

  • Bacterial Proteins
  • DNA, Bacterial
  • beta-Lactamases
  • carbapenemase