Association between the effacing (eae) gene and the Shiga-like toxin-encoding genes in Escherichia coli isolates from cattle.
Two hundred ninety-six Escherichia coli isolates from feces or intestines of calves with diarrhea were hybridized with 7 gene probes. One probe (the eae probe) was derived from the eae gene coding for a protein involved in the effacement of the enterocyte microvilli by the group of bacteria called attaching and effacing E coli (AEEC), and 2 probes were derived from genes coding for the Shiga-like toxins (SLT) 1 and 2 produced by the verocytotoxic E coli (VTEC). The other 4 probes were derived from DNA sequences associated with the adhesive properties of enteroadherent E coli (EAEC) to cultured cells (the EAF probe for the localized adherence pattern, probes F1845 and AIDA-1 for the diffuse adherence pattern, and the Agg probe for the aggregative adherence pattern). Hybridization results for the eae probe were in agreement, for all but 1 of the 8 isolates, with previously published phenotypic results of microvilli effacement. The latter was previously reported as effacing the microvilli of calf enterocytes, but was eae probe-negative. Two classes of isolates hybridized with the eae probe. Members of a first class (60 isolates) additionally produced a positive signal with 1 or both of the SLT probes (VTEC-AEEC isolates). Isolates hybridizing with the eae and the SLT1 probes were the most frequent: 56 isolates (ie, 93% of all VTEC-AEEC). Members of the second class (10 isolates) failed to hybridize with either SLT probe (non-VTEC-AEEC isolates).(ABSTRACT TRUNCATED AT 250 WORDS)
Mainil
J G
JG
Department of Bacteriology, Faculty of Veterinary Medecine, University of Liège, Sart-Tilman, Belgium.
Jacquemin
E R
ER
Kaeckenbeeck
A E
AE
Pohl
P H
PH
D000818:Animals; D001427:Bacterial Toxins / Q000235:genetics*; D002417:Cattle / Q000382:microbiology*; D015342:DNA Probes; D004273:DNA, Neoplasm / Q000235:genetics; D004768:Enterotoxins / Q000235:genetics*; D004926:Escherichia coli / Q000145:classification / Q000235:genetics* / Q000302:isolation & purification; D005798:Genes, Bacterial; D010957:Plasmids; D015183:Restriction Mapping; D012703:Serotyping; D022622:Shiga Toxin 1; D022641:Shiga Toxin 2
D001427:Bacterial Toxins; D015342:DNA Probes; D004273:DNA, Neoplasm; D004768:Enterotoxins; D022622:Shiga Toxin 1; D022641:Shiga Toxin 2