Extended-spectrum beta-lactamase-producing Shiga toxin gene (stx1)-positive Escherichia coli O91:H14 carrying blaCTX-M-15 on an IncI1-ST31 plasmid isolated from a human patient in Germany

Int J Med Microbiol. 2015 May;305(3):404-7. doi: 10.1016/j.ijmm.2015.03.003. Epub 2015 Mar 6.


In 2011, the Shiga toxin- and extended-spectrum β-lactamase (ESBL)-producing Escherichia coli O104:H4 caused a serious outbreak of gastroenteritis in Germany. This strain carried bla(CTX-M-15) and bla(TEM-1) on an IncI1-ST31 plasmid. During screening of individuals at risk for acquisition of the epidemic E. coli O104:H4, we isolated another ESBL-producing and Shiga toxin-positive E. coli belonging to serotype O91:H14 from feces of a human patient. Interestingly, the patient also carried a further ESBL-producing but Shiga toxin-negative E. coli. Both strains harbored bla(CTX-M-15) and bla(TEM-1) on an IncI1-ST31 plasmid, which was indistinguishable regarding size and plasmid restriction pattern from the plasmid of the epidemic E. coli O104:H4 strain. The patient had traveled to India 6 months prior to the isolation of the E. coli strains. This is the first report of an ESBL-producing, Shiga toxin-positive E. coli of serogroup O91. Our data suggest a high propensity of the IncI1-ST31 plasmid to spread in the human and/or animal population.

Keywords: Antimicrobial resistance; Conjugative transfer; E. coli; ESBL; Shiga toxin.

MeSH terms

  • DNA, Bacterial / genetics
  • Escherichia coli Infections / microbiology*
  • Escherichia coli Proteins / genetics
  • Escherichia coli Proteins / metabolism*
  • Feces / microbiology*
  • Gene Transfer, Horizontal
  • Germany
  • Humans
  • India
  • Molecular Weight
  • Plasmids / analysis*
  • Restriction Mapping
  • Serotyping
  • Shiga-Toxigenic Escherichia coli / classification
  • Shiga-Toxigenic Escherichia coli / enzymology*
  • Shiga-Toxigenic Escherichia coli / genetics
  • Shiga-Toxigenic Escherichia coli / isolation & purification*
  • Travel
  • beta-Lactamases / genetics
  • beta-Lactamases / metabolism*


  • DNA, Bacterial
  • Escherichia coli Proteins
  • beta-Lactamases
  • beta-lactamase CTX-M, E coli