Escherichia coli K-12 can utilize an exogenous γ-glutamyl peptide as an amino acid source, for which γ-glutamyltranspeptidase is essential

Abstract

Escherichia coli K-12 can utilize a γ-glutamyl peptide as an amino acid source, for which γ-glutamyl-transpeptidase (EC 2.3.2.2) is essential. We suggest that the γ-glutamyl linkage of a γ-glutamyl peptide is hydrolyzed by γ-glutamyltranspeptidase located in the periplasmic space, and the released amino acid is taken up and utilized by E. coli.