Thrombocytin, a serine protease from Bothrops atrox venom. 1. Purification and characterization of the enzyme

Journal Article · Tue Aug 07 00:00:00 EDT 1979 · Biochemistry; (United States)

DOI:https://doi.org/10.1021/bi00583a020· OSTI ID:5424077

Kirby, E P ^[1]; Niewiarowski, S; Stocker, K; Kettner, C; Shaw, E; Brudzynsi, T M

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1. Temple Univ. Health Sciences Center, Philadelphia, PA

Thrombocytin, a platelet-activating enzyme from Bothrops atrox venom, has been purified to homogeneity by precipitation with sodium salicylate and chromatography on heparin-agarose. Thrombocytin is a single-chain glycoprotein with a molecular weight of 36,000 which contains 5.6% carbohydrate. It causes platelet aggregation, release of platelet serotonin, and activation of factor XIII. The most sensitive substrate for the amidolytic activity of thrombocytin was Tos-Gly-Pro-Arg-p-nitroanilide hydrochloride. The activity of thrombocytin on this substrate and on platelets was inhibited by diisopropyl fluorophosphate (DFP), soybean trypsin inhibitor, and several arginine chloromethyl ketones. Active site titration with nitrophenyl guanidinobenzoate demonstrated that approximately 86% of the preparation was in the active form. These experiments demonstrate the presence of serine and histidine in the active site of thrombocytin and suggest that thrombocytin is a classical serine protease with a platelet-activating activity similar to thrombin.

• OSTI ID: 5424077
• Journal Information: Biochemistry; (United States), Vol. 18:16
• Country of Publication: United States
• Language: English

Related Subjects

59 BASIC BIOLOGICAL SCIENCES
PEPTIDE HYDROLASES
ENZYME ACTIVITY
PURIFICATION
VENOMS
BIOLOGICAL PATHWAYS
AGGLOMERATION
AMINO ACIDS
BLOOD PLATELETS
CHROMATOGRAPHY
ELECTROPHORESIS
ENZYME INHIBITORS
EXPERIMENTAL DATA
GLUCOPROTEINS
HISTIDINE
KETONES
MOLECULAR WEIGHT
PRECIPITATION
SERINE
SEROTONIN
SNAKES
TABLES
TRYPSIN
AMINES
ANIMALS
AZOLES
BIOLOGICAL MATERIALS
BLOOD
BLOOD CELLS
BODY FLUIDS
CARBOHYDRATES
CARBOXYLIC ACIDS
DATA
DATA FORMS
DRUGS
ENZYMES
HETEROCYCLIC ACIDS
HETEROCYCLIC COMPOUNDS
HYDROLASES
HYDROXY ACIDS
HYDROXY COMPOUNDS
IMIDAZOLES
INDOLES
INFORMATION
MATERIALS
NUMERICAL DATA
ORGANIC ACIDS
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
PROTEINS
PYRROLES
RADIOPROTECTIVE SUBSTANCES
REPTILES
RESPONSE MODIFYING FACTORS
SACCHARIDES
SEPARATION PROCESSES
SYMPATHOMIMETICS
TRYPTAMINES
VERTEBRATES
550200* - Biochemistry