Carboxypeptidase B catalyzes hydrolysis of the basic amino acids lysine, arginine and histidine from the C-terminal end of polypeptides. The molecular weight is 33.8kD, pI is 6.0 and the optimum pH is 7.5-9.0. Carboxypeptidase B is competitively inhibited by arginine and lysine. The enzyme is also inhibited by metal chelating agents, e.g., EDTA. SAB has cloned rat carboxypeptidase B gene into  E.coli for expression with equivalent properties compared to animal original carboxypeptidase B .Recombinant carboxypeptidase B can replace native carboxypeptidase B for using in a variety of biotechnological processes.