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 (By similarity). 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 Sulfur metabolism; glutathione metabolism. Heterodimer composed of the light and heavy chains. The active site is located in the light chain (By similarity). Induced upon nitrogen starvation and oxidative stress. Cleaved by autocatalysis into a large and a small subunit. Belongs to the gamma-glutamyltransferase family.