title: Occurrence of the temperature-sensitive hemagglutinin among avian Escherichia coli.
abstract: In this study, we determined the occurrence of the tsh gene among 305 Escherichia coli isolates from chickens by means of the polymerase chain reaction and agglutination of chicken erythrocytes; 200 of those isolates were obtained from chickens with colisepticemia, 52 isolates were from lesions of cellulitis, and 53 were from feces of normal chickens. The tsh gene was found in 79 (39.5%) isolates from colisepticemia, in 10 (19%) cellulitis-derived E. coli isolates, and in two (3.8%) fecal isolates. Among the tsh+ strains, 68 (86%) isolates from colisepticemia and nine (90%) from cellulitis agglutinated chicken erythrocytes in the presence of mannose, after growing the strains on colonization factor antigen agar plates at 26 C, which confirms a correlation between mannose-resistant hemagglutination and expression of hemagglutinin Tsh. These results show, for the first time, the presence of the gene tsh in cellulitis-derived E. coli isolates; the high frequency of this gene among avian pathogenic E. coli isolates in Brazil indicates that its putative role as a virulence factor should be studied more thoroughly.
authors.affiliation: Depto de Microbiologia, Universidade Estadual de Londrina, Parana, Brazil.
authors.forename: Elaine R
authors.initials: ER
authors.lastname: Delicato
authors.forename: Benito Guimarães
authors.initials: BG
authors.lastname: de Brito
authors.forename: Anna Paula
authors.initials: AP
authors.lastname: Konopatzki
authors.forename: Luis Carlos J
authors.initials: LC
authors.lastname: Gaziri
authors.forename: Marilda C
authors.initials: MC
authors.lastname: Vidotto
mesh_terms: D018830:Adhesins, Escherichia coli / Q000302:isolation & purification*; D000818:Animals; D016470:Bacteremia / Q000382:microbiology / Q000662:veterinary; D002481:Cellulitis / Q000382:microbiology / Q000662:veterinary; D002645:Chickens; D004926:Escherichia coli / Q000235:genetics / Q000472:pathogenicity*; D004927:Escherichia coli Infections / Q000382:microbiology / Q000662:veterinary*; D005243:Feces / Q000382:microbiology; D006386:Hemagglutination Tests / Q000662:veterinary; D006388:Hemagglutinins / Q000302:isolation & purification*; D016133:Polymerase Chain Reaction / Q000379:methods / Q000662:veterinary; D011201:Poultry Diseases / Q000382:microbiology*; D013696:Temperature; D014774:Virulence / Q000235:genetics
chemical_list: D018830:Adhesins, Escherichia coli; D006388:Hemagglutinins; C112027:tsh protein, E coli