A common antigenic determinant found in two functionally unrelated toxins

• Published in: The Journal of experimental medicine Vol. 160; no. 4; pp. 1253 - 1258
• Main Authors: GARIEPY, J, ÓHANLEY, P, WALDMAN, S. A, MURAD, F, SCHOOLNIK, G. K
• Format: Journal Article
• Language: English
• Published: New York, NY Rockefeller University Press 01.10.1984; The Rockefeller University Press
• Subjects: Amino Acid Sequence; Animals; Antitoxins - pharmacology; Bacterial Toxins; Bacteriology; Biological and medical sciences; Conotoxins; Cross Reactions; Enterotoxins - analysis; Enterotoxins - immunology; Enterotoxins - toxicity; Epitopes - analysis; Epitopes - immunology; Escherichia coli Proteins; Female; Fundamental and applied biological sciences. Psychology; Mice; Microbiology; Mollusk Venoms - analysis; Mollusk Venoms - immunology; Mollusk Venoms - toxicity; Muscle Hypotonia - etiology; Paralysis - etiology; Pathogenicity, virulence, toxins, bacteriocins, pyrogens, host-bacteria relations, miscellaneous strains; Rabbits; Snails; Antigenic determinant; Peptides; Tertiary structure; Escherichia coli; Animal origin; Homology; Primary structure; Gastropoda; Common antigen; Marine environment; Proteins; Toxin; Synthetic product; Antigenicity; Structure activity relation; Disulfide bond; Neurotoxin; Bacteria; Invertebrata; Mollusca; Escherichieae; Enterobacteriaceae
• ISSN: 0022-1007; 1540-9538
• DOI: 10.1084/jem.160.4.1253

The heat-stable enterotoxin ST Ib produced by enterotoxigenic E. coli strains shares a sequence homology with the sea snail neurotoxin, conotoxin GI. Rabbit antisera were raised against synthetic analogs of these toxins and to a six-residue peptide representing the region common to both toxins. Results from enzyme-linked immunosorbent assays indicate that the homologous region of both toxins represents part of their antigenic site. The lack of cross-reactivity exhibited by the six-residue common domain with serum directed against either toxin suggests that this region probably retains a similar conformation in the intact toxins but not in the isolated fragment.