Angiotensin-converting enzyme

EC=3.4.15.1
Alternative name(s):
Dipeptidyl carboxypeptidase I
Kininase II
CD_antigen=CD143
Cleaved into the following chain:
Angiotensin-converting enzyme, soluble form

Function

Converts angiotensin I to angiotensin II by release of the terminal His-Leu, this results in an increase of the vasoconstrictor activity of angiotensin. Also able to inactivate bradykinin, a potent vasodilator. Has also a glycosidase activity which releases GPI-anchored proteins from the membrane by cleaving the mannose linkage in the GPI moiety.

Catalytic activity

Release of a C-terminal dipeptide, oligopeptide-|-Xaa-Yaa, when Xaa is not Pro, and Yaa is neither Asp nor Glu. Thus, conversion of angiotensin I to angiotensin II, with increase in vasoconstrictor activity, but no action on angiotensin II.

Cofactor

Binds 2 zinc ions per subunit. Isoform Testis-specific only binds 1 zinc ion per subunit.
Binds 3 chloride ions per subunit.

Enzyme regulation

Strongly activated by chloride. Specifically inhibited by lisinopril, captopril and enalaprilat.

Tissue specificity

Ubiquitously expressed, with highest levels in lung, kidney, heart, gastrointestinal system and prostate. Isoform Testis-specific is expressed in spermatocytes and adult testis.