Genes coding for Shiga-like toxins in bovine verotoxin-producing Escherichia coli (VTEC) strains belonging to different O:K:H serotypes.
Forty-six verotoxin-producing Escherichia coli (VTEC) strains isolated from diarrhoeic and healthy calves in Spain were examined for DNA sequences homologous to genes for verotoxins (VT1 and VT2) and enterotoxins (LT-I, LT-II, STaH, STaP and STb). Hybridisation showed that 26 (57%) of VTEC strains carried VT1 genes, 13 (28%) possessed VT2 genes, and 7 (15%) carried both VT1 and VT2 genes. No VTEC strains hybridised with DNA probes for enterotoxins. A correlation was found between the serotype and type of VT produced. Thus, all strains of serotypes O26:K-:H11 (13 strains), O103:K-:H2 (3 strains) and O128:K?:H- (4 strains) hybridised with the VT1 probe only, whereas all strains of serotypes O4:K-:H4 (3 strains) and O113:K-:H21 (4 strains) were positive with the VT2 probe only. By contrast, O81:K?:H28 (2 strains) and O157:K-:H- (2 strains) strains hybridised with both VT1 and VT2 probes. One strain of serotype O157:K-:H7 was VT2 positive.
Blanco
M
M
Departamento de Microbiología y Parasitología, Facultad de Veterinaria, Universidad de Santiago, Lugo, Spain.
Blanco
J
J
Blanco
J E
JE
González
E A
EA
Gomes
T A
TA
Zerbini
L F
LF
Yano
T
T
de Castro
A F
AF
D000818:Animals; D001427:Bacterial Toxins / Q000096:biosynthesis* / Q000235:genetics*; D002417:Cattle / Q000382:microbiology*; D002418:Cattle Diseases / Q000382:microbiology; D015342:DNA Probes; D003967:Diarrhea / Q000382:microbiology / Q000662:veterinary; D004197:Disease Reservoirs; D004768:Enterotoxins / Q000235:genetics; D004926:Escherichia coli / Q000145:classification / Q000235:genetics* / Q000472:pathogenicity; D005798:Genes, Bacterial; D006801:Humans; D012703:Serotyping; D022622:Shiga Toxin 1; D022641:Shiga Toxin 2; D013030:Spain
D001427:Bacterial Toxins; D015342:DNA Probes; D004768:Enterotoxins; D022622:Shiga Toxin 1; D022641:Shiga Toxin 2