Comparative study of colony hybridization with synthetic oligonucleotide probes and enzyme-linked immunosorbent assay for identification of enterotoxigenic Escherichia coli.
On the basis of the published nucleotide sequences of the genes that code for the heat-labile toxin LTh and the heat-stable toxins STaI and STaII of human enterotoxigenic Escherichia coli, a 34-mer and two 33-mer oligonucleotide probes were synthesized. To compare their relative efficacies in the detection and differentiation of enterotoxigenic E. coli, a colony hybridization technique using these probes and a GM1 ganglioside enzyme-linked immunosorbent assay using monoclonal anti-LT and anti-ST antibodies were used with 76 strains of E. coli with known enterotoxin profiles. For further evaluation of probe specificity, the enterotoxigenic bacteria Vibrio cholerae O1 and non-O1 and Yersinia enterocolitica were examined with the colony hybridization technique. The sensitivity of colony hybridization compared favorably with that of GM1 ganglioside enzyme-linked immunosorbent assay, and the two assays showed a high level of concordance in specific detection and differentiation of E. coli with various enterotoxin profiles (kappa = 0.906, P less than 0.00001). The probes did not hybridize with DNAs from strains of V. cholerae O1 or non-O1 or Y. enterocolitica.
Sommerfelt
H
H
Medical Department B, University of Bergen, Haukeland Hospital, Norway.
Svennerholm
A M
AM
Kalland
K H
KH
Haukanes
B I
BI
Bjorvatn
B
B
D000818:Animals; D000911:Antibodies, Monoclonal; D001427:Bacterial Toxins / Q000032:analysis* / Q000235:genetics; D001483:Base Sequence; D004269:DNA, Bacterial / Q000235:genetics*; D004768:Enterotoxins / Q000032:analysis* / Q000235:genetics; D004797:Enzyme-Linked Immunosorbent Assay; D004926:Escherichia coli / Q000032:analysis / Q000235:genetics / Q000302:isolation & purification*; D029968:Escherichia coli Proteins; D006801:Humans; D009693:Nucleic Acid Hybridization; D009838:Oligodeoxyribonucleotides / Q000235:genetics; D013552:Swine
D000911:Antibodies, Monoclonal; D001427:Bacterial Toxins; D004269:DNA, Bacterial; D004768:Enterotoxins; D029968:Escherichia coli Proteins; D009838:Oligodeoxyribonucleotides; C034151:heat stable toxin (E coli); C027538:heat-labile enterotoxin, E coli