Esterase activity of rabbit pulmonary angiotensin converting enzyme |
| |
Authors: | W M Keung B Holmquist J F Riordan |
| |
Institution: | 1. Biophysics Research Laboratory Department of Biological Chemistry Harvard Medical School Boston, MA 02115 USA;2. the Brigham and Women''s Hospital Boston, MA 02115 USA |
| |
Abstract: | A series of depsipeptides have been synthesized and used to demonstrate the esterase activity of rabbit pulmonary angiotensin converting enzyme. Among the esters studied, Bz-Phe-OPhe-Ala was found to have the highest which is about that of its exact peptide analog, Bz-Phe-Phe-Ala. Esters such as Bz-Gly-OGly-Phe, Bz-Gly-OPhe-Phe and Bz-Gly-OLeu-Ala were also hydrolyzed but at much lower rates. Normal Michaelis-Menten behavior is observed and the kinetic parameters obtained indicate that the esters and their peptide analogs bind to the enzyme equally well, but that peptides are hydrolyzed at much higher rates. Studies on the pH-rate profiles, chloride ion effect, inhibition and chemical modifications detect no mechanistic differences between ester and peptide hydrolysis. |
| |
Keywords: | ACE angiotensin converting enzyme Bz benzoyl OLeu 2-hydroxyisocaproic acid OPhe 2-phenyllactic acid OGly glycolic acid hepes N-2-hydroxyethylpiperazine-N′-2-ethane-sulfonic acid |
本文献已被 ScienceDirect 等数据库收录! |