γ-glutamyl transferase is an enzyme that transfers gamma-glutamyl functional groups. It is found in many tissues, the most notable one being the liver, and has significance in medicine as a diagnostic marker. GGT catalyzes the transfer of the gamma-glutamyl moiety of glutathione to an acceptor that may be an amino acid, a peptide or water (forming glutamate). GGT plays a key role in the gamma-glutamyl cycle, a pathway for the synthesis and degradation of glutathione and drug and xenobiotic detoxification. Other lines of evidence indicate that GGT can also exert a prooxidant role, with regulatory effects at various levels in cellular signal transduction and cellular pathophysiology.
γ-GT, Native (Equine)
Enzyme Commission Number
5-12 units/mg solid
One unit will liberate 1.0 μmole of p-nitroaniline from L-γ-glutamyl-p-nitroanilide per min at pH 8.5 at 25°C.
EC 188.8.131.52; glutamyl transpeptidase; α-glutamyl transpeptidase; γ-glutamyl peptidyltransferase; γ-glutamyl transpeptidase (ambiguous); γ-GPT; γ-GT; γ-GTP; L-γ-glutamyl transpeptidase; L-γ-glutamyltransferase; L-glutamyltransferase; GGT (ambiguous); γ-glutamyltranspeptidase (ambiguous); γ-glutamyltransferase; 9046-27-9; GGTP