Purification and partial characterization of a thrombin-like/gyroxin enzyme from bushmaster (Lachesis muta rhombeata) venom

A. S. Aguiar, C. R. Alves, A. R. Melgarejo and S. Giovanni-De-Simone. Purification and partial characterization of a thrombin-like/gyroxin enzyme from bushmaster (Lachesis muta rhombeata) venom. Toxicon 34, 555-565, 1996.-The acidic coagulating enzyme of the L. m. rhombeata venom was purified to homogeneity using one step on preparative isoelectric focusing followed by gel permeation on a high performance liquid chromatography system. The enzyme focused with pIs 3.1-5.0 and had a molecular mass of 47,000 mel. wt as determined by high performance liquid gel-filtration chromatography and about 45,000 mel. wt as judged by sodium dodecyl sulfate-polyacrylamide-gel electrophoresis. The enzyme is a glycoprotein containing sialic acid and 12.4% of neutral carbohydrates. The 30 N-terminal amino acid sequence of the L. m. rhombeata protein shows 100% identity with L. m. muta gyroxin and considerable sequence homology with gyroxin and thrombin-related proteins. The enzyme exhibits strong N-p-tosyl-L-arginine methyl esterase activity, hydrolyses tripeptide nitroanilide derivatives weakly or not at all, and cleaves specifically the fibropeptide A (alpha-chain). Copyright (C) 1996 Elsevier Science Ltd.