Aminopeptidase P, Capable of Hydrolyzing Oligoproline, from Bovine Brain

Abstract

An aminopeptidase P, capable of hydrolyzing oligoproline, was isolated from the homogenate of bovine brain. The molecular mass of the enzyme was 140kDa by gel filtration. The enzyme was activated by Mn²⁺ and inhibited by o-phenanthroline. The enzyme hydrolyzed substrates such as Pro-Pro-Pro-Pro, Pro-Pro-Pro, and Pro-Pro to proline, and cleaved N-terminal amino acids from pep-tides containing penultimate prolines such as bradykinin and neuro-peptide Y.