not indentical to renin, cathepsin G, tonin, enzyme I, enzyme II, the calcium-dependent angiotensin I-converting enzyme or the calcium-independent carboxy peptidase; inhibited by alpha-1-antitrypsin, diisopropylfluorophosphate & lima bean trypsin inhibitor; not inhibited by Captopril, Teprotide or Enalapril; pH optinum=7.7