Catalyzes the transfer of the gamma-glutamyl moiety of glutathione (GSH) and other gamma-glutamyl compounds to amino acids and peptides. Major GSH-degrading enzyme, catalyzing the hydrolytic release of L-glutamate from GSH. Plays a role in the turnover of the vacuolar GSH, serving as an alternative nitrogen source during nitrogen starvation. an alpha-amino acid + an N-terminal (5-L-glutamyl)-[peptide] = 5-L-glutamyl amino acid + N-terminal L-alpha-aminoacyl-[peptide] glutathione + H2O = L-cysteinylglycine + L-glutamate an S-substituted glutathione + H2O = an S-substituted L-cysteinylglycine + L-glutamate Activity is decreased by glutathione and ammonium ion. Sulfur metabolism; glutathione metabolism. Heterodimer composed of a light and a heavy chain. The active site is located in the light chain. Induced upon nitrogen starvation. Repressed by ammonium ions. 6-diazo-5-oxo-L-norleucine and L-azaserine are irreversible inhibitors whereas serine-borate is a reversible inhibitor. Cleaved by autocatalysis into a large and a small subunit. Present with 672 molecules/cell in log phase SD medium. Belongs to the gamma-glutamyltransferase family.