Which of the following best describes angiotensin conveing enzyme?
High-Yield Explanation
Angiotensin conveing enzyme is a zinc containing protease that cleaves carboxy terminus dipeptides from from angiotensin I and bradykinin. Also know: Angiotensin conveing enzyme is a dipeptidyl carboxypeptidase which splits off histidyl-leucine from the physiologically inactive angiotensin I forming the octapeptide angiotensin II. It also inactivates bradykinin. ACE is an ectoenzyme which exists in two forms i.e a somatic form found throughout the body and a germinal form found in postmeiotic spermatogenic cells and spermatozoa. Germinal ACE is a 90-kDa protein that has only one extracellular domain and active site. Somatic ACE is a 170-kDa protein with two homologous extracellular domains, each containing an active site. Ref: Ganong's Review of Medical Physiology, 24e, chapter 38