Differences in bindings to the GM1 receptor by heat-labile enterotoxin of human and porcine Escherichia coli strains.
Heat-labile enterotoxin producing strains of Escherichia coli were isolated from diarrheal faeces of humans and from the jejunum of pigs which had died of diarrhea. The heat-labile enterotoxin was assayed by three different enzyme-linked immunosorbent assays (ELISA). The first assay was based upon immunological cross-reactions between the heat-labile enterotoxins of E coli and Vibrio cholerae, the second on specific E coli heat-labile enterotoxin antibodies and the third on affinity of the toxin to the presumed cell membrane receptor, the ganglioside GM1. The heat-labile enterotoxins of human and porcine origin bound equally well to the same extent in the ELISA procedure, which utilized immunological cross-reactivity between the heat-labile enterotoxins of E coli and V cholerae. The reactivity, however, was quite different in the GM1-ELISA. The binding affinity was high between GM1 and enterotoxin produced by E coli strains of human origin, whereas the binding affinity was low for enterotoxin from porcine strains.
D000818:Animals; D000907:Antibodies, Bacterial / Q000276:immunology; D001667:Binding, Competitive; D003967:Diarrhea / Q000382:microbiology; D004768:Enterotoxins / Q000378:metabolism*; D004797:Enzyme-Linked Immunosorbent Assay; D004926:Escherichia coli / Q000378:metabolism*; D005677:G(M1) Ganglioside / Q000378:metabolism*; D005732:Gangliosides / Q000378:metabolism*; D006801:Humans; D013552:Swine / Q000382:microbiology
D000907:Antibodies, Bacterial; D004768:Enterotoxins; D005732:Gangliosides; D005677:G(M1) Ganglioside