title: Properties of the arginine esterases from Bitis nasicornis (horned adder) venom.
abstract: Five forms of arginine esterase (DE-2 to DE-6) were purified from Bitis nasicornis venom by gel filtration on Sephadex G-50, followed by ion exchange chromatography on CM-cellulose and DEAE-sepharose. They contain 17.6 to 23.1% of carbohydrate, 242 to 244 amino acids including 14 half-cystine residues and have molecular masses of about 38 kDa. The enzymes have a high esterolytic activity towards N alpha-benzoyl-L-arginine ethyl ester but show no proteolytic activity against Azocoll and no clotting activity against fibrinogen. Their sequences of the first 19 amino-terminal residues are the same, but their carbohydrate content shows some variation. Furthermore, sequence studies on the N-terminal regions of the arginine esterases from B. nasicornis venom indicate that they share a significant degree of sequence homology with the kallikrein-like enzymes of Crotalus adamanteus and C. atrox venoms and also with porcine pancreatic kallikrein. Studies on tryptic glycopeptides of the arginine esterases show that carbohydrate occurs at the N-terminal region of the molecule and also towards the center.
mesh_terms: D000595:Amino Acid Sequence; D002265:Carboxylic Ester Hydrolases / Q000032:analysis*; D055598:Chemical Phenomena; D002621:Chemistry; D002627:Chemistry, Physical; D006868:Hydrolysis; D007610:Kallikreins / Q000032:analysis; D010084:Oxidation-Reduction; D014357:Trypsin; D014757:Viper Venoms / Q000032:analysis*
chemical_list: D014757:Viper Venoms; C019724:arginine esterase; D002265:Carboxylic Ester Hydrolases; D007610:Kallikreins; D014357:Trypsin