Carboxypeptidase D can refer to one of several enzymes. A family of serine carboxypeptidases (i.e. enzymes that use an active site serine residue) includes (EC 3.4.16.6, cereal serine
carboxypeptidase II, Saccharomyces cerevisiae KEX1 gene product, carboxypeptidase Kex1, gene KEX1 serine carboxypeptidase, KEX1 carboxypeptidase, KEX1 proteinase, KEX1DELTAp, CPDW-II, serine
carboxypeptidase, Phaseolus proteinase) is an enzyme. This enzyme has an optimal pH of 4.5-6.0, is inhibited by diisopropyl fluorophosphate,
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