Characterisation of clinical and food animal Escherichia coli isolates producing CTX-M-15 extended-spectrum β-lactamase belonging to ST410 phylogroup A

Int J Antimicrob Agents. 2011 Apr;37(4):365-7. doi: 10.1016/j.ijantimicag.2011.01.001. Epub 2011 Feb 16.


Seven phylogroup A CTX-M-15-producing Escherichia coli isolates recovered from clinical and meat samples were further characterised. All of them belonged to sequence type ST410. Only 2 of the 22 virulence genes investigated were detected. All isolates carried the fimH gene encoding type 1 fimbriae, and five isolates harboured the iucD gene encoding aerobactin siderophore. A group of five isolates showed 81.2% similarity by pulsed-field gel electrophoresis (PFGE), comprising three clinical isolates belonging to ONT:H9 and two food isolates belonging to O55:H9. Different HpaI digestion patterns were observed for plasmids, but all of them belonged to IncFIB group and harboured bla(CTX-M-15) associated with bla(OXA-1), bla(TEM), tetA, catB3 and aac(6')-Ib surrounded by an identical genetic environment. These findings showed the possibility of lateral gene transfer of bla(CTX-M-15) as well as other antibiotic resistance determinants between low-virulence food and clinical isolates.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Base Sequence
  • DNA Primers
  • Electrophoresis, Gel, Pulsed-Field
  • Escherichia coli / classification
  • Escherichia coli / enzymology
  • Escherichia coli / isolation & purification*
  • Food Microbiology*
  • Nucleic Acid Hybridization
  • Polymerase Chain Reaction
  • beta-Lactamases / biosynthesis*


  • DNA Primers
  • beta-Lactamases