GGT1 Immunizing Blocking Peptide

The enzyme encoded by this gene is a type I gamma-glutamyltransferase that catalyzes the transfer of the glutamyl moiety of glutathione to a variety of amino acids and dipeptide acceptors. The enzyme is composed of a heavy chain and a light chain, which are derived from a single precursor protein. It is expressed in tissues involved in absorption and secretion and may contribute to the etiology of diabetes and other metabolic disorders. Multiple alternatively spliced variants have been identified. There are a number of related genes present on chromosomes 20 and 22, and putative pseudogenes for this gene on chromosomes 2, 13, and 22. [provided by RefSeq, Jan 2014]

GGT1: Initiates extracellular glutathione (GSH) breakdown, provides cells with a local cysteine supply and contributes to maintain intracellular GSH level. It is part of the cell antioxidant defense mechanism. Catalyzes the transfer of the glutamyl moiety of glutathione to amino acids and dipeptide acceptors. Alternatively, glutathione can be hydrolyzed to give Cys-Gly and gamma glutamate. Isoform 3 seems to be inactive. Defects in GGT1 are a cause of glutathionuria (GLUTH); also known as gamma-glutamyltranspeptidase deficiency. It is an autosomal recessive disease. Belongs to the gamma-glutamyltransferase family. 3 isoforms of the human protein are produced by alternative promoter.

Protein type: EC 3.4.19.13; Other Amino Acids Metabolism - selenoamino acid; Other Amino Acids Metabolism - glutathione; Other Amino Acids Metabolism - cyanoamino acid; EC 3.4.19.14; Lipid Metabolism - arachidonic acid; Membrane protein, integral; Transferase; EC 2.3.2.2; Other Amino Acids Metabolism - taurine and hypotaurine

Chromosomal Location of Human Ortholog: 22q11.23

Cellular Component: anchored to external side of plasma membrane; extracellular space; integral to membrane; plasma membrane

Molecular Function: gamma-glutamyltransferase activity; protein binding

Biological Process: amino acid metabolic process; cysteine biosynthetic process; glutamate metabolic process; glutathione biosynthetic process; glutathione catabolic process; glutathione metabolic process; leukotriene biosynthetic process; leukotriene metabolic process; regulation of immune system process; regulation of inflammatory response; spermatogenesis; xenobiotic metabolic process; zymogen activation

Disease: Glutathionuria