Snake venom serine protease that has fibrinogenolytic activities. Preferentially cleaves the Bbeta-chain (FGB) and more slowly the Aa-chain (FGA) of fibrinogen, but does not affect the gamma-chain. Has also fibrinolytic activity. May play a role in antithrombotic reaction as well as thrombolytic reaction. The fibrinolytic activity is completely inhibited by PMSF, diisopropylfluorophosphate (DFP), pefabloc, dithiothreitol (DTT) and Zn(2+), but not by Pepstatin A, E64, iodoacetate, chymostatin, tosyl-Lphenylalanine chloromethyl ketone (TPCK), soybean trypsin inhibitor (SBTI), phosphoramidon, Ca(2+), Co(2+), Cu(2+), Fe(2+), Mg(2+), Mn(2+), K(+), and Na(+). Optimum pH is from 5.5 to 8.5. Heterodimer of the brevinase A chain and the brevinase B chain. Expressed by the venom gland. Is devoid of fibrinogen clotting and caseinolytic activities. Belongs to the peptidase S1 family. Snake venom subfamily.