title: Virulence profiling and genetic relatedness of Shiga toxin-producing Escherichia coli isolated from humans and ruminants.
abstract: In the present study the occurrence, genotypic characteristics and relatedness of Shiga toxin-producing Escherichia coli (STEC) isolated from 235 fecal samples of diarrheic children (n=75), sheep (n=80), and cattle (n=80) were investigated. Overall, STEC was found in 4%, 61.2%, and 18.7% of diarrheic children, sheep and cattle, respectively. Three of the four STEC isolates from diarrheic children yielded the stx1/ehly profile. The predominant virulence profile of sheep isolates was stx1/ehly (85.2%), but cattle isolates were heterogeneous. Genetic relatedness and diversity of 36 selected isolates were analyzed by enterobacterial repetitive consensus sequences fingerprinting (ERIC) and phylogrouping. In total, 19 ERIC-types were observed in humans (n=2), sheep (n=5), and cattle (n=12) isolates. The majority of the sheep STEC were assigned into B1 phylogroup (83.3%), but cattle isolates belonged to different phylogroups with B1 predominance. Three human STEC isolates had the major characteristics of sheep isolates but revealed distinct fingerprint. These findings indicate that cattle can potentially carry a diverse group of STEC strains.
authors.affiliation: Department of Pathobiology, Faculty of Veterinary Medicine, Garmsar Branch, Islamic Azad University, Garmsar, Iran. Electronic address: askari@iau-garmsar.ac.ir.
authors.forename: Mahdi
authors.initials: M
authors.lastname: Askari Badouei
authors.affiliation: Department of Pathobiology, Faculty of Veterinary Medicine, Garmsar Branch, Islamic Azad University, Garmsar, Iran.
authors.forename: Maziar
authors.initials: M
authors.lastname: Jajarmi
authors.affiliation: Department of Microbiology, Faculty of Medicine, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Akbar
authors.initials: A
authors.lastname: Mirsalehian
mesh_terms: D000818:Animals; D002417:Cattle; D002648:Child; D002675:Child, Preschool; D016172:DNA Fingerprinting / Q000379:methods; D004927:Escherichia coli Infections / Q000382:microbiology*; D005838:Genotype; D006801:Humans; D012418:Ruminants; D012756:Sheep; D054323:Shiga-Toxigenic Escherichia coli / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification / Q000472:pathogenicity*; D014774:Virulence / Q000235:genetics; D037521:Virulence Factors / Q000235:genetics*
chemical_list: D037521:Virulence Factors
keywords: Cattle; ERIC; Human; Phylogroup; STEC; Sheep; Virulence