ACE2 is a metalloproteinase and a homolog of carboxypeptidase ACE. It hydrolyzes a variety of angiotensin peptides and is the main active peptide of the renin-angiotensin system (RAS).([3]) ACE2, which is made of 805 amino acids, is a type I transmembrane glycoprotein with a single extracellular catalytic domain. This article is protected by copyright.