title: Amino acid sequence and characterization of C-type lectin purified from the snake venom of Crotalus ruber.
abstract: Galactoside-binding lectin was purified from the snake venom of Crotalus ruber by affinity chromatography on a lactose-agarose column, and the complete amino acid sequence was determined. The C. ruber venom lectin (CRL) showed a single band of 28 kDa by SDS-polyacrylamide electrophoresis under non-reducing conditions, but it showed a single band of 15 kDa under reducing conditions, indicating that CRL is a disulfide-linked homodimer of 15 kDa subunit. CRL specifically recognized beta-galactosides such as thiodigalactoside followed by N-acetylgalactosamine when examined with their inhibitory effects on CRL-induced hemagglutination. A CRL subunit was composed of 135 residues containing nine Cys residues and showed a high similarity to other C-type galactoside-binding lectins from snake venoms. C. atrox lectin (CAL) showed almost the same sequence except for eight amino acid residues. Neither CRL nor CAL induced platelet aggregation by itself or inhibited platelet aggregation mediated by von Willebrand factor or fibrinogen with agonists. CRL showed a similar oligomeric form and the sugar specificity as CAL, but it showed different divalent cation sensitivity such as Mn(2+) and Ni(2+). Homology modeling suggested that the amino acid substitution found in CRL does not affect sugar recognition of the lectin but might alter the conformation and influence the sugar binding pocket induced by the metal-ion binding.
authors.affiliation: Course of Medical Communication, Fujita Health University College Toyoake, Aichi 470-1192, Japan.
authors.forename: Jiharu
authors.initials: J
authors.lastname: Hamako
authors.forename: Yukiyo
authors.initials: Y
authors.lastname: Suzuki
authors.forename: Nobuhiro
authors.initials: N
authors.lastname: Hayashi
authors.forename: Mina
authors.initials: M
authors.lastname: Kimura
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Ozeki
authors.forename: Keiichiro
authors.initials: K
authors.lastname: Hashimoto
authors.forename: Taei
authors.initials: T
authors.lastname: Matsui
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D002241:Carbohydrates / Q000737:chemistry; D002412:Cations / Q000737:chemistry; D002846:Chromatography, Affinity; D003435:Crotalid Venoms / Q000737:chemistry* / Q000302:isolation & purification; D006801:Humans; D037181:Lectins, C-Type / Q000737:chemistry* / Q000235:genetics / Q000302:isolation & purification / Q000502:physiology; D008969:Molecular Sequence Data; D010974:Platelet Aggregation; D017434:Protein Structure, Tertiary; D017386:Sequence Homology, Amino Acid; D013329:Structure-Activity Relationship
chemical_list: D002241:Carbohydrates; D002412:Cations; D003435:Crotalid Venoms; D037181:Lectins, C-Type