Thrombin-like snake venom serine protease that has fibrinogen-clotting activity (FGA or FGB). Its activity is inhibited by diisopropylfluorophosphate (DFP) and PMSF, whereas EDTA has no effect on it. Monomer. Expressed by the venom gland. Glycosylated. Does not act on factor X, prothrombin and plasminogen. Belongs to the peptidase S1 family. Snake venom subfamily.