Reported Gamma Glutamyl Activation of Peptide-Bond Synthesis

Abstract

IN a recent paper in Nature, Hanes et al.¹ postulated a γ-glutamyl transfer mechanism in peptide bond synthesis. It is suggested that the amino-acid forms its first peptide bond with the α-carboxyl of glutamic acid by displacing the cysteinyl glycine from glutathione. The amino-acid, now peptide bound, could be further transferred to other peptides. The concept is strengthened in view of the universal and yet unexplained presence of glutathione in all living tissues, the great significance of ‘transferring’ reactions in biochemistry, and the need for some hypothesis to shed light on the mechanism of protein synthesis. Experiments to test this hypothesis are described in this communication.