title: Prevalence of four enterotoxin (STaP, STaH, STb, and LT) and four adhesin subunit (K99, K88, 987P, and F41) genes among Escherichia coli isolates from cattle.
abstract: Colony hybridizations with DNA probes for 3 heat-stable (STaP, STaH, and STb) enterotoxins and 1 heat-labile (LT) enterotoxin and for 4 adhesins (K99, F41, K88, 987P) were performed on 870 Escherichia coli isolates to determine pathotypes prevalent among enterotoxigenic E coli (ETEC) isolated from cattle in Belgium. One hundred thirty-two E coli isolates (15.2%) hybridized with probes STaP, K99, and/or F41. The 5 other probes were not hybridized by E coli isolates. Therefore, only STaP enterotoxin and K99 and F41 adhesins were virulence factors of ETEC isolated from cattle. Two major pathotypes accounted for 95% of the ETEC: STaP+K99+F41+ (67.4%) and STaP+K99+ (27.3%). The last 5% of probe-positive isolates had STaP+, STaP+F41+, or K99+F41+ minor pathotypes. Of 12 American ETEC isolates also assayed, 7 were positive with STb and/or 987P probes (pathotypes STaP+STb+, STaP+ 987P+, or STaP+STb+987P+) and may be porcine- rather than bovine-specific enteropathogens. The remaining 5 American ETEC isolates belonged to 3 minor pathotypes (STaP+, STaP+F41+, and K99+F41+) also found among Belgian E coli isolates. Such isolates may be derivatives of STaP+K99+F41+ or STaP+K99+ ETEC after in vivo or in vitro loss of virulence genes and/or non-ETEC isolates, which have acquired virulence genes by in vivo transfer.
authors.affiliation: Department of Bacteriology, Faculty of Veterinary Medicine, University of Liège, Brussels, Belgium.
authors.forename: J G
authors.initials: JG
authors.lastname: Mainil
authors.forename: F
authors.initials: F
authors.lastname: Bex
authors.forename: E
authors.initials: E
authors.lastname: Jacquemin
authors.forename: P
authors.initials: P
authors.lastname: Pohl
authors.forename: M
authors.initials: M
authors.lastname: Couturier
authors.forename: A
authors.initials: A
authors.lastname: Kaeckenbeeck
mesh_terms: D018830:Adhesins, Escherichia coli; D000818:Animals; D001425:Bacterial Outer Membrane Proteins / Q000235:genetics*; D001427:Bacterial Toxins / Q000235:genetics*; D015373:Bacterial Typing Techniques; D002417:Cattle; D015342:DNA Probes; D004768:Enterotoxins / Q000235:genetics*; D004926:Escherichia coli / Q000235:genetics*; D029968:Escherichia coli Proteins; D005798:Genes, Bacterial / Q000235:genetics*; D013045:Species Specificity
chemical_list: D018830:Adhesins, Escherichia coli; D001425:Bacterial Outer Membrane Proteins; D001427:Bacterial Toxins; D015342:DNA Probes; D004768:Enterotoxins; D029968:Escherichia coli Proteins; C034151:heat stable toxin (E coli); C027538:heat-labile enterotoxin, E coli