Purification and characterization of brevinase, a heterogeneous two-chain fibrinolytic enzyme from the venom of Korean snake, Agkistrodon blomhoffii brevicaudus

A fibrinolytic enzyme, designated as brevinase, was purified from the venom of Korean snake, Agkistrodon blomhoffii brevicaudus. Brevinase cleaved bot h the A alpha- and B beta-chains of fibrinogen but did not affect the gamma -chain. It showed beta-fibrinogenase activity devoid of fibrinogen clotting and caseinolytic activity. The fibrinolytic activity was completely inhibi ted by PMSF, DFP, Pefabloc, and DTT, indicating brevinase is a serine prote ase requiring disulfide bridge(s) for its activity. It kept 80% of the init ial activity after heating at 100 degrees C for 3 min, showed an equal maxi mum activity in the pH range from 5.5 to 8.5, and was inactivated by Zn2+. Brevinase consists of two polypeptide chains of 16.5 and 17 kDa linked by d isulfide bridge(s). The N-terminal amino acid sequences of 16.5 and 17 kDa chains showed homology to the N-terminal and the internal (central region) amino acid sequences of single-chain fibrinolytic enzymes in snake venom, r espectively. (C) 1999 Academic Press.