Cl-
ACE2 activity is regulated by chloride ions. The presence of chloride increases the hydrolysis of angiotensin I by ACE2, but inhibits cleavage of the vasoconstrictor angiotensin II
Cl-
binding ligands are Tyr207 and Arg514, possible model for chloride activation, effect is substrate dependent: activation with angiotensin I and (7-methoxycoumarin-4-yl)acetyl-APK(2,4-dinitrophenyl)-OH, inhibition with angiotensin II
Cl-
enhances activity by about 10fold
Cl-
required, highest activity at 1.5 M NaCl
F-
enhances activity by about 10fold
Zinc
zinc carboxypeptidase
Zn2+
contains zinc-binding consensus sequence HEXXH, amino acids 374-378, zinc-binding protease