1. Molecular characterization of Escherichia coli O157:H7 strains isolated from different sources and geographic regions.
- Author
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Regua-Mangia AH, Gonzalez AG, Cerqueira AM, and Andrade JR
- Subjects
- Animals, Argentina epidemiology, Brazil epidemiology, Cattle, Cattle Diseases epidemiology, Enterohemorrhagic Escherichia coli genetics, Enterohemorrhagic Escherichia coli pathogenicity, Escherichia coli O157 pathogenicity, Food Microbiology, Gene Expression Regulation, Bacterial physiology, Genetic Markers, Humans, Polymerase Chain Reaction veterinary, Shiga Toxin 1 genetics, Shiga Toxin 1 metabolism, Shiga Toxin 2 genetics, Shiga Toxin 2 metabolism, Virulence, Cattle Diseases microbiology, Enterohemorrhagic Escherichia coli isolation & purification, Escherichia coli O157 genetics, Escherichia coli O157 isolation & purification
- Abstract
Escherichia (E.) coli serotype O157:H7 is a globally distributed human enteropathogen and is comprised of microorganisms with closely related genotypes. The main reservoir for this group is bovine bowels, and infection mainly occurs after ingestion of contaminated water and food. Virulence genetic markers of 28 O157:H7 strains were investigated and multilocus enzyme electrophoresis (MLEE) was used to evaluate the clonal structure. O157:H7 strains from several countries were isolated from food, human and bovine feces. According to MLEE, O157:H7 strains clustered into two main clonal groups designated A and B. Subcluster A1 included 82% of the O157:H7 strains exhibiting identical MLEE pattern. Most enterohemorrhagic E. coli (EHEC)O157:H7 strains from Brazil and Argentina were in the same MLEE subgroup. Bovine and food strains carried virulence genes associated with EHEC pathogenicity in humans.
- Published
- 2012
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