Microorganisms (Jul 2023)

Shiga-Toxin-Producing Strains of <i>Escherichia coli</i> O104:H4 and a Strain of O157:H7, Which Can Cause Human Hemolytic Uremic Syndrome, Differ in Biofilm Formation in the Presence of CO<sub>2</sub> and in Their Ability to Grow in a Novel Cell Culture Medium

  • Kei Amemiya,
  • David A. Rozak,
  • Jennifer L. Dankmeyer,
  • William R. Dorman,
  • Charles Marchand,
  • David P. Fetterer,
  • Patricia L. Worsham,
  • Brett K. Purcell

DOI
https://doi.org/10.3390/microorganisms11071744
Journal volume & issue
Vol. 11, no. 7
p. 1744

Abstract

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One pathogen that commonly causes gastrointestinal illnesses from the consumption of contaminated food is Escherichia coli O157:H7. In 2011 in Germany, however, there was a prominent outbreak of bloody diarrhea with a high incidence of hemolytic uremic syndrome (HUS) caused by an atypical, more virulent E. coli O104:H4 strain. To facilitate the identification of this lesser-known, atypical E. coli O104:H4 strain, we wanted to identify phenotypic differences between it and a strain of O157:H7 in different media and culture conditions. We found that E. coli O104:H4 strains produced considerably more biofilm than the strain of O157:H7 at 37 °C (p = 0.0470–0.0182) Biofilm production was significantly enhanced by the presence of 5% CO2 (p = 0.0348–0.0320). In our study on the innate immune response to the E. coli strains, we used HEK293 cells that express Toll-like receptors (TLRs) 2 or 4. We found that E. coli O104:H4 strains had the ability to grow in a novel HEK293 cell culture medium, while the E. coli O157:H7 strain could not. Thus, we uncovered previously unknown phenotypic properties of E. coli O104:H4 to further differentiate this pathogen from E. coli O157:H7.

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