title: Animal Enterotoxigenic Escherichia coli.
abstract: Enterotoxigenic Escherichia coli (ETEC) is the most common cause of E. coli diarrhea in farm animals. ETEC are characterized by the ability to produce two types of virulence factors: adhesins that promote binding to specific enterocyte receptors for intestinal colonization and enterotoxins responsible for fluid secretion. The best-characterized adhesins are expressed in the context of fimbriae, such as the F4 (also designated K88), F5 (K99), F6 (987P), F17, and F18 fimbriae. Once established in the animal small intestine, ETEC produce enterotoxin(s) that lead to diarrhea. The enterotoxins belong to two major classes: heat-labile toxins that consist of one active and five binding subunits (LT), and heat-stable toxins that are small polypeptides (STa, STb, and EAST1). This review describes the disease and pathogenesis of animal ETEC, the corresponding virulence genes and protein products of these bacteria, their regulation and targets in animal hosts, as well as mechanisms of action. Furthermore, vaccines, inhibitors, probiotics, and the identification of potential new targets by genomics are presented in the context of animal ETEC.
authors.affiliation: Faculté de Médecine Vétérinaire, Université de Montréal, Québec J2S 7C6, Canada.
authors.forename: J Daniel
authors.initials: JD
authors.lastname: Dubreuil
authors.affiliation: Department of Veterinary and Biomedical Sciences, University of Minnesota, St. Paul, MN 55108.
authors.forename: Richard E
authors.initials: RE
authors.lastname: Isaacson
authors.affiliation: School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA 19104.
authors.forename: Dieter M
authors.initials: DM
authors.lastname: Schifferli
mesh_terms: D018829:Adhesins, Bacterial; D018830:Adhesins, Escherichia coli / Q000378:metabolism; D000818:Animals; D000829:Animals, Domestic / Q000382:microbiology; D002417:Cattle / Q000382:microbiology; D003967:Diarrhea / Q000382:microbiology / Q000662:veterinary; D004285:Dogs / Q000382:microbiology; D054307:Enterotoxigenic Escherichia coli / Q000235:genetics / Q000472:pathogenicity*; D004768:Enterotoxins / Q000145:classification / Q000378:metabolism; D004927:Escherichia coli Infections / Q000453:epidemiology / Q000382:microbiology / Q000662:veterinary*; D010861:Fimbriae, Bacterial / Q000145:classification / Q000235:genetics / Q000378:metabolism; D012756:Sheep / Q000382:microbiology; D013552:Swine / Q000382:microbiology; D013553:Swine Diseases / Q000382:microbiology; D014481:United States / Q000453:epidemiology; D014774:Virulence; D037521:Virulence Factors / Q000235:genetics* / Q000378:metabolism
chemical_list: D018829:Adhesins, Bacterial; D018830:Adhesins, Escherichia coli; D004768:Enterotoxins; D037521:Virulence Factors