Distribution of putative adhesins in Shiga toxin-producingEscherichia coli(STEC) strains isolated from different sources in Chile

Abstract
SUMMARY: The distribution of three putative adhesin genes in 123 Shiga toxin-producing (STEC) strains was determined by PCR. The STEC strains were isolated from human patients (n=90) and food (n=33) and were characterized by serogroup, virulence markers (eae,stx1,stx2) and adherence factors (efa1,lpfAO157,saa) genes. Serogroups O157 (64·4%) and O26 (28·8%) were the most frequent among human strains and the majority (60·6%) of food strains were serologically non-typable. The adhesin genesefa1 (90%) andlpfAO157(73·3%) were the most common in humans strains andsaa(45·5%) in food strains. The presence of these genes in addition toeaein STEC from different sources may suggest a relevant role in their pathogenesis.