Description
Carboxypeptidase B (EC 3.4.17.2, protaminase, pancreatic carboxypeptidase B, tissue carboxypeptidase B, peptidyl-L-lysine [L-arginine]hydrolase) is a carboxypeptidase that preferentially acts upon basic amino acids, such as arginine and lysine. This serum enzyme is also responsible for rapidly metabolizing the C5a protein into C5a des-Arg, with one less amino acid.Three different procarboxypeptidases A and two different procarboxypeptidases B have been isolated. The B1 and B2 forms differ from each other mainly in isoelectric point. Carboxypeptidase B1 is a highly tissue-specific protein and is a useful serum marker for acute pancreatitis and dysfunction of pancreatic transplants. It is not elevated in pancreatic carcinoma