IntEnz

EC 3.4.11.3 - Cystinyl aminopeptidase

IntEnz Enzyme Nomenclature
EC 3.4.11.3

Names

Reaction

• Release of an N-terminal amino acid, CysXaa-, in which the half-cystine residue is involved in a disulfide loop, notably in oxytocin or vasopressin. Hydrolysis rates on a range of aminoacyl arylamides exceed that for the cystinyl derivative, however.

Cofactor

• Zn²⁺

Comments:

A zinc-containing sialoglycoprotein in peptidase family M1 (membrane alanyl aminopeptidase family).

Links to other databases

References

1. Sjöholm, I.
   Biochemical studies on oxytocin and oxytocinase.
   Acta Pharm. Suec. 4 : 81-96 (1967). [PMID: 6041057]
2. Sjöholm, I. and Yman, L.
   Degradation of oxytocin, lysine vasopressin, angiotensin II, and angiotensin II amide by oxytocinase (cystine aminopeptidase).
   Acta Pharm. Suec. 4 : 65-76 (1967). [PMID: 4292447]
3. Yman, L.
   Studies on human serum aminopeptidase. Some properties of oxytocinase, human serum aminopeptidase A and leucine aminopeptidase and their purification from retroplacental serum.
   Acta Pharm. Suec. 7 : 75-86 (1970). [PMID: 5421622]
4. Sakura, H., Lin, T.Y., Doi, M., Mizutani, S. and Kawashima, Y.
   Purification and properties of oxytocinase, a metalloenzyme.
   Biochem. Int. 2 : 173-179 (1981).

[EC 3.4.11.3 created 1972]