Merck, GS63-100UG, GST A3-3, Recombinant Human

General description
using spectrophotometric determination of 1-chloro-2,4-dinitrobenzene (CDNB) conjugation with reduced glutathione (1 mM) in 100 mM NaPO4 (pH 6.5) at room temperature.
Biochem/physiol Actions
Glutathione S-transferase alpha 3 (GSTA3) is an enzyme that in humans is encoded by the GSTA3 gene. Glutathione S-transferases (GSTs) are a family of enzymes that play an important role in detoxification by catalyzing the conjugation of many hydrophobic and electrophilic compounds with reduced glutathione. Based on their biochemical, immunologic, and structural properties, cytosolic and membrane-bound forms of glutathione S-transferase are encoded by two distinct supergene families. 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. The GSTs are thought to function in xenobiotic metabolism and play a role in susceptibility to cancer, and other diseases.
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.
Preparation Note
The enzyme should be used by the end-user customer within 1 year of receipt.