Leucine Aminopeptidase Activity

Abstract

LEUCINE aminopeptidase is a proteolytic enzyme that is capable of hydrolyzing L-leucyl peptides. It is widely distributed in bacteria, plants and animals and has been demonstrated in all human tissues assayed, with high activity in the duodenum, kidney and liver.^{1 2 3} The intracellular function of this enzyme is not known but probably involves hydrolysis of a peptide bond near an L-leucine residue or the transfer of L-leucine from one peptide molecule to another. In the small intestine this peptidase is active in the terminal phases of protein digestion. We have demonstrated it regularly in gastric juice, bile and duodenal secretion, in . . .