Escherichia coli heat-stable enterotoxin b (STb) in vivo internalization within rat intestinal epithelial cells.
Heat-stable enterotoxin b (STb) is a low molecular weight toxin known to bind sulfatide, its receptor. The fate of STb bound to rat intestinal epithelium cells was followed using an anti-toxin gold labeled assay and transmission electron microscopy. The data suggest that STb toxin and the fusion protein maltose binding protein (MBP)-STb were internalized whereas its mutant I41 E-M42R with reduced hydrophobicity did not show internalization. There was a significant difference in the mean of gold particles per field between rat intestine incubated with STb or the fusion protein MBP-STb and the negative control consisting of intestine incubated with PBS alone. No subcellular compartment seems to be particularly aimed by the toxin as gold particles were randomly distributed within the cell.
Labrie
Vincent
V
Département de Pathologie et Microbiologie, Faculté de Médecine Vétérinaire, Université de Montreal, Saint-Hyacinthe, Québec, Canada.
Harel
Josée
J
Dubreuil
J Daniel
JD
D000818:Animals; D001427:Bacterial Toxins / Q000378:metabolism*; D004768:Enterotoxins / Q000378:metabolism* / Q000502:physiology; D004847:Epithelial Cells / Q000378:metabolism*; D004926:Escherichia coli / Q000378:metabolism*; D029968:Escherichia coli Proteins; D007413:Intestinal Mucosa / Q000378:metabolism*; D008854:Microscopy, Electron / Q000662:veterinary; D008970:Molecular Weight; D051381:Rats; D011993:Recombinant Fusion Proteins / Q000378:metabolism*
D001427:Bacterial Toxins; D004768:Enterotoxins; D029968:Escherichia coli Proteins; D011993:Recombinant Fusion Proteins; C034151:heat stable toxin (E coli)