title: The intestinal zonula occludens toxin (ZOT) receptor recognises non-native ZOT conformers and localises to the intercellular contacts.
abstract: A preliminary structural analysis of Vibrio cholerae zonula occludens toxin (ZOT) was made by equilibrium denaturation and circular dichroism. ZOT is a structurally unstable protein in aqueous solution (DeltaG((H2O)) 3.82 kcal/mol), the putative intra- and extracellular domains unfold co-operatively, with complete denaturation via observed conformational intermediates. Refolding of denatured ZOT is not dependent on disulphide bridge formation. Partial refolding of a maltose binding protein-ZOT fusion did not prevent its specific binding to the ZOT receptor on Caco-2 cells. Immuno-gold labelling showed that the ZOT receptor localises to the intercellular contacts between cells in a confluent monolayer.
authors.affiliation: Pharmaceutical Sciences, Institute for Biomedical Sciences, University of Strathclyde, 27 Taylor Street, Glasgow, G4 0NR, UK.
authors.forename: Alvin
authors.initials: A
authors.lastname: Lee
authors.forename: Natalie
authors.initials: N
authors.lastname: White
authors.forename: Christopher F
authors.initials: CF
authors.lastname: van der Walle
mesh_terms: D018938:Caco-2 Cells; D002772:Cholera Toxin / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D002942:Circular Dichroism; D004731:Endotoxins; D006046:Gold; D019791:Guanidine / Q000494:pharmacology; D006801:Humans; D007150:Immunohistochemistry / Q000379:methods; D007413:Intestinal Mucosa / Q000378:metabolism; D008855:Microscopy, Electron, Scanning; D011485:Protein Binding; D011489:Protein Denaturation; D020673:Protein Renaturation; D011956:Receptors, Cell Surface / Q000378:metabolism*; D011993:Recombinant Fusion Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D013816:Thermodynamics; D019108:Tight Junctions / Q000378:metabolism*; D014734:Vibrio cholerae / Q000737:chemistry
chemical_list: D004731:Endotoxins; D011956:Receptors, Cell Surface; D011993:Recombinant Fusion Proteins; C402827:zonula occludens toxin receptor; C077728:zonula occludens toxin, Vibrio cholerae; D006046:Gold; D002772:Cholera Toxin; D019791:Guanidine