GST A3-3 Assay Kit

Cytosolic and membrane-bound forms of glutathione S-transferase are encoded by two distinct supergene families. These enzymes are involved in cellular defense against toxic, carcinogenic, and pharmacologically active electrophilic compounds. At present, eight distinct classes of the soluble cytoplasmic mammalian glutathione S-transferases have been identified: alpha, kappa, mu, omega, pi, sigma, theta and zeta. This gene encodes a glutathione S-tranferase belonging to the alpha class genes that are located in a cluster mapped to chromosome 6. Genes of the alpha class are highly related and encode enzymes with glutathione peroxidase activity. However, during evolution, this alpha class gene diverged accumulating mutations in the active site that resulted in differences in substrate specificity and catalytic activity. The enzyme encoded by this gene catalyzes the double bond isomerization of precursors for progesterone and testosterone during the biosynthesis of steroid hormones. An additional transcript variant has been identified, but its full length sequence has not been determined. [provided by RefSeq, Jul 2008]

GSTA3: Conjugation of reduced glutathione to a wide number of exogenous and endogenous hydrophobic electrophiles. Catalyzes isomerization reactions that contribute to the biosynthesis of steroid hormones. Efficiently catalyze obligatory double-bond isomerizations of delta(5)-androstene-3,17-dione and delta(5)- pregnene-3,20-dione, precursors to testosterone and progesterone, respectively. Belongs to the GST superfamily. Alpha family.

Protein type: EC 2.5.1.18; Xenobiotic Metabolism - metabolism by cytochrome P450; Xenobiotic Metabolism - drug metabolism - cytochrome P450; Transferase; Other Amino Acids Metabolism - glutathione

Chromosomal Location of Human Ortholog: 6p12.1

Cellular Component: cytosol

Molecular Function: glutathione transferase activity

Biological Process: glutathione metabolic process; xenobiotic metabolic process