Angiotensin-converting enzyme: new concepts concerning its biological role

Angiotensin-converting enzyme (ACE, EC 3.4.15.1) is a zinc metalloprotease catalyzing the hydrolysis of carboxy-terminal dipeptides from oligopeptide substrates, most notably the decapeptide angiotensin I (AI) and the nonapeptide bradykinin (BK). ACE is a component of the renin-angiotensin system (RAS), and in view of recent advances in understanding of the physiology and pathophysiology of the RAS, it is important that the implications of these new concepts are explored in terms of what is known about the biochemistry of ACE. Further, there has been a dramatic increase in the use of potent orally effective, active-site-directed ACE inhibitors in the absence of a complete understanding of the molecular basis for their activity or of the full physiological significance of their use.