Specificity of ε-peptidase of Achromobacter pestifer EA

Abstract

The enzyme ε-acylase/peptidase isolated from Achromobacter pestifer EA was stereospecific for the ε-amide or ε-peptide bonds of L-lysine. The configuration and nature of the amino acid coupled to the ε-amino group of lysine influenced the ε-peptidase activity. The enzymic activity was present if the α-NH₂ and α-COOH groups of ε-benzoyl L-lysine and ε- L-phenylalanyl-L-lysine were coordinated with cobalt. The activity was greatly reduced when they were coordinated with copper and was reactivated by the addition of 2-mercaptoethanol or EDTA. The enzymic activity was reduced but not lost if the α-NH₂ group was acylated or involved in peptide bond formation. Upon esterification of the α-COOH group with methyl or benzyl groups, the activity was completely lost; there was not much loss of activity when the α-COOH group was combined as a peptide.