Rat brain enkephalinase: characterization of the active site using mercaptopropanoyl amino acid inhibitors, and comparison with angiotensin-converting enzyme.

Over fifty mercaptopropanoyl amino acids and related derivatives were synthesized to define the steric, electronic and stereochemical requirements for binding to the active site of enkephalinase (ENKASE), and also for their ability to inhibit angiotensin-converting enzyme (ACE). In this way the character of ENKASE and ACE active sites were compared.