Gamma-glutamyltranspeptidase (IPR000101)

Short name: GGT_peptidase

Overlapping homologous superfamilies

Family relationships



Gamma-glutamyltranspeptidase (EC: (GGT) [PMID: 2868390] 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 [PMID: 1378736]. In prokaryotes and eukaryotes, it is an enzyme that consists of two polypeptide chains, a heavy and a light subunit, processed from a single chain precursor by an autocatalytic cleavage. The active site of GGT is known to be located in the light subunit. The sequences of mammalian and bacterial GGT show a number of regions of high similarity [PMID: 2570061]. Pseudomonas cephalosporin acylases (EC:3.5.1) that convert 7-beta-(4-carboxybutanamido)-cephalosporanic acid (GL-7ACA) into 7-aminocephalosporanic acid (7ACA) and glutaric acid are evolutionary related to GGT and also show some GGT activity [PMID: 1358202]. Like GGT, these GL-7ACA acylases, are also composed of two subunits.

As an autocatalytic peptidase GGT belongs to MEROPS peptidase family T3 (gamma-glutamyltransferase family, clan PB(T)). The active site residue for members of this family and family T1 is C-terminal to the autolytic cleavage site. The type example is gamma-glutamyltransferase 1 from Escherichia coli.

GO terms

Biological Process

GO:0006751 glutathione catabolic process

Molecular Function

GO:0036374 glutathione hydrolase activity

Cellular Component

No terms assigned in this category.

Contributing signatures

Signatures from InterPro member databases are used to construct an entry.
PROSITE patterns