Carboxypeptidase Z (CPZ)

Carboxypeptidase Z is a member of the metallocarboxypeptidase family. This enzyme displays carboxypeptidase activity towards substrates with basic C-terminal residues. It is most active at neutral pH and is inhibited by active site-directed inhibitors of metallocarboxypeptidases. Alternative splicing in the coding region results in multiple transcript variants encoding different isoforms.

The 390-residue carboxypeptidase domain of CPZ shares 49% amino acid identity with CPE and CPN1 and is followed by a unique C-terminal region. When expressed in a baculovirus system, CPZ displayed carboxypeptidase activity towards substrates with C-terminal basic residues. On Western blots, CPZ migrated as a 71-kD protein.