title: Purification and characterization of two platelet-aggregation inhibitors, named angustatin and H-toxin TA(2), from the venom of Dendroaspis angusticeps.
abstract: Angustatin and H-toxin TA2 were purified from unfractionated Dendroaspis angusticeps venom (0.3 g) using S-Sepharose fast flow column chromatography, gelfiltration on a Sephadex G-50 column, and reverse-phase HPLC. The purified materials strongly inhibited ADP-induced platelet aggregation. The primary structure of angustatin was determined by the Edman degradation of peptides derived from digestions with endopeptidese Arg-C and α-chymotrypsin. Angustatin, which was composed of 59 amino acid residues and an RGD sequence, was identified as a short-length inhibitor similar to mambin, dendroaspin, echistatin, and eristicophin. Angustatin shared 83%, 17%, and 15% homologies with mambin, eristicophin, and echistatin, respectively. On the other hand, H-toxin TA2 did not conserve the RGD sequence in its structure; it was replaced for the Glu-Met-Leu sequence. Furthermore, the amino acid sequence of H-toxin TA2 corresponded to toxin TA2, excluding the amino acid residue of His28Arg.
authors.affiliation: Department of Hygienic Chemistry, Meiji Pharmaceutical University, 2-522-1, Noshio, Kiyose, Tokyo 204-8588, Japan. Electronic address: oyama@my-pharm.ac.jp.
authors.forename: Etsuko
authors.initials: E
authors.lastname: Oyama
authors.affiliation: Emeritus Professor of Meiji Pharmaceutical University, 2-522-1, Noshio, Kiyose, Tokyo 204-8588, Japan.
authors.forename: Hidenobu
authors.initials: H
authors.lastname: Takahashi
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002851:Chromatography, High Pressure Liquid; D004546:Elapid Venoms / Q000032:analysis / Q000737:chemistry* / Q000302:isolation & purification; D017815:Elapidae; D008969:Molecular Sequence Data; D010975:Platelet Aggregation Inhibitors / Q000032:analysis / Q000302:isolation & purification*; D017422:Sequence Analysis, DNA
chemical_list: D004546:Elapid Venoms; C000600550:H-toxin TA2, Dendroaspis angusticeps; D010975:Platelet Aggregation Inhibitors; C000600549:angustatin, Dendroaspis angusticeps
keywords: Inhibitor; Neurotoxin; Platelet aggregation; Snake venom