Enzymic Splitting and Synthesis of Glutathione

Abstract

THE mechanism of the activation of the enzymic splitting of glutathione by glutamine—first considered specific for the amide¹—may be interpreted as the transfer of the glutamyl moiety from glutathione to glutamine with the formation of the corresponding γ-glutamylglutamine^2–5. Since it was considered possible that the γ-glutamylglutamine formed from glutathione and glutamine may serve as substrate for glutamotransferase, which can utilize glutamine only^6–9, a detailed study of the activation of the enzymic splitting of glutathione by L-amino-acids and peptides as well as of the effect of γ-glutamyl peptides on the splitting was undertaken. In the experiments to be reported, an extract from sheep kidney, purified by butanol treatment¹⁰ and ammonium sulphate fractionation, served as source of the enzymes. In a similar manner potent enzyme solutions were prepared from brain cortex and liver.