Open AccessShiga Toxin 2e-Producing Escherichia coli Isolates from Humans and Pigs Differ in Their Virulence Profiles and Interactions with Intestinal Epithelial Cells
Author(s) -
Anne-Katharina Sonntag,
Martina Bielaszewska,
Alexander Mellmann,
Nadine Dierksen,
Peter Schierack,
Lothar H. Wieler,
M. Alexander Schmidt,
Helge Karch
Publication year - 2005
Publication title -
applied and environmental microbiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.552
H-Index - 324
eISSN - 1070-6291
pISSN - 0099-2240
DOI - 10.1128/aem.71.12.8855-8863.2005
Subject(s) - virulence , bacterial adhesin , microbiology and biotechnology , biology , escherichia coli , shiga toxin , toxin , diarrhea , enterobacteriaceae , shiga like toxin , virology , gene , genetics , medicine
ThirteenEscherichia coli strains harboringstx 2e were isolated from 11,056 human stools. This frequency corresponded tothe presence of thestx 2e allele in 1.7% of allShiga toxin-producingE. coli (STEC) strains. The strainsharboringstx 2e were associated with mild diarrhea(n = 9) or asymptomatic infections (n =4). Because STEC isolates possessingstx 2e are porcine pathogens, we compared the humanSTEC isolates withstx 2e -harboringE.coli isolated from piglets with edema disease and postweaningdiarrhea. All pig isolates possessed the gene encoding the F18 adhesin,and the majority possessed adhesin involved in diffuse adherence; theseadhesins were absent from all the human STEC isolates. In contrast, thehigh-pathogenicity island encoding an iron uptake system was found onlyin human isolates. Host-specific patterns of interaction withintestinal epithelial cells were observed. All human isolates adheredto human intestinal epithelial cell lines T84 and HCT-8 but not to pigintestinal epithelial cell line IPEC-J2. In contrast, the pig isolatescompletely lysed human epithelial cells but not IPEC-J2 cells, to whichmost of them adhered. Our data demonstrate thatE. coli isolates producing Shiga toxin 2e have imported specific virulence andfitness determinants which allow them to adapt to the specific hosts inwhich they cause various forms ofdisease.