title: Primary structure of two-chain botrocetin, a von Willebrand factor modulator purified from the venom of Bothrops jararaca.
abstract: The complete amino acid sequence and location of the disulfide bonds of two-chain botrocetin, which promotes platelet agglutination in the presence of von Willebrand factor, from venom of the snake Bothrops jararaca are presented. Sequences of the alpha and beta subunits were determined by analysis of peptides generated by digestion of the S-pyridylethylated protein with Achromobacter protease I or alpha-chymotrypsin and by chemical cleavage with cyanogen bromide or 2-(2'-nitrophenylsulfenyl)-3-methyl-3-bromoindolenine. Two-chain botrocetin is a heterodimer composed of the alpha subunit (consisting of 133 amino acid residues) and the beta subunit (consisting of 125 amino acid residues) held together by a disulfide bond. Seven disulfide bonds link half-cystine residues 2 to 13, 30 to 128, and 103 to 120 of the alpha subunit; 2 to 13, 30 to 121, and 98 to 113 of the beta subunit; and 80 of the alpha subunit to 75 of the beta subunit. In terms of amino acid sequence and disulfide bond location, two-chain botrocetin is homologous to echinoidin (a sea urchin lectin) and other C-type (Ca(2+)-dependent) lectins.
authors.affiliation: Division of Biomedical Polymer Science, School of Medicine, Fujita Health University, Aichi, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Usami
authors.forename: Y
authors.initials: Y
authors.lastname: Fujimura
authors.forename: M
authors.initials: M
authors.lastname: Suzuki
authors.forename: Y
authors.initials: Y
authors.lastname: Ozeki
authors.forename: K
authors.initials: K
authors.lastname: Nishio
authors.forename: H
authors.initials: H
authors.lastname: Fukui
authors.forename: K
authors.initials: K
authors.lastname: Titani
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D003435:Crotalid Venoms / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology; D003553:Cystine / Q000737:chemistry; D006388:Hemagglutinins / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology; D037102:Lectins / Q000737:chemistry; D008969:Molecular Sequence Data; D010446:Peptide Fragments / Q000737:chemistry; D011487:Protein Conformation; D017386:Sequence Homology, Amino Acid; D012911:Snakes; D014841:von Willebrand Factor / Q000187:drug effects
chemical_list: D003435:Crotalid Venoms; D006388:Hemagglutinins; D037102:Lectins; D010446:Peptide Fragments; D014841:von Willebrand Factor; D003553:Cystine; C030961:botrocetin