T9698

Thioredoxin Reductase from rat liver

buffered aqueous glycerol solution, ≥100 units/mg protein (Bradford)

• Synonym(s): NADPH:Oxidised Thioredoxin Oxidoreductase, Thioredoxin: NADP⁺ Oxidoreductase
• CAS Number: 9074-14-0
• UNSPSC Code: 12352200
• NACRES: NA.32
• EC Number: 1.8.1.9 (BRENDA, IUBMB)
• MDL number: MFCD00678149
• Form: buffered aqueous glycerol solution
• Assay: ≥90% (GE)
• Biological source: rat liver
• Mol wt: 55—67 kDa

Properties

• biological source: rat liver
• Quality Segment: 200
• assay: ≥90% (GE)
• form: buffered aqueous glycerol solution
• specific activity: ≥100 units/mg protein (Bradford)
• mol wt: 55—67 kDa
• technique(s): activity assay: suitable
• impurities: Glutathione reductase
• solubility: water: soluble
• suitability: suitable for molecular biology
• UniProt accession no.: O89049
• shipped in: dry ice
• storage temp.: −20°C
• Gene Information: rat ... Txnrd1(58819)

Description

General description

Research area: Cell signaling

Application

Thioredoxin Reductase from rat liver can be used for studying the uptake and reduction of a-lipoic acid by utilizing reducing capacity of human erythrocytes.[1] The product can also be used for studying the activation mechanism of transglutaminase 2 (TG2) in the extracellular matrix by using Thioredoxin.[2]

Biochem/physiol Actions

Thioredoxin Reductase is a ubiquitous enzyme that catalyzes the active site disulfide of thioredoxin by NADPH.[3] The product also reduces ubiquinone and regenerates ubiquinol, a powerful antioxidant.[4]

Thioredoxin reductase (TrxR) is a NADPH-dependent oxidoreductase containing one FAD per subunit that reduces the active site disulfide in oxidized thioredoxin (Trx).

Thioredoxin reductase (TrxR) is a NADPH-dependent oxidoreductase containing one FAD per subunit that reduces the active site disulfide in oxidized thioredoxin (Trx). The molecular weight of the isozymes from mammalian sources vary between 55-67 kDa as compared with 35 kDa in prokaryotes, plants or yeast. The substrate specificity of the mammalian enzyme is much broader than the prokaryotic enzyme reducing both mammalian and E. coli thioredoxins as well as non-disulfide substrates such selenite, lipoic acids, lipid hydroperoxides, and hydrogen peroxide.

Thioredoxin reductase from mammalian sources contains a selenocysteine residue that is essential for the activity of the enzyme. It is one of the antioxidant enzymes present in the mammalian cell together with catalase, glutathione peroxidase and superoxide dismutase, and helps in removal of reactive oxygen species (ROS) from the cell. An example is the removal of excess nitric oxide (NO) by the formation of a complex with glutathione forming the S-nitroso-glutathione adduct (GS-NO). This can be cleaved directly by thioredoxin reductase. Hydrogen peroxide, another deleterious oxidant in the cell, is also reduced directly by mammalian TrxR.

Physical form

Solution in 50 mM Tris-HCl, pH 7.5, 300 mM NaCl, 1 mM EDTA, and 10% glycerol.

Other Notes

One unit will cause an increase in absorbance of 1.0 at 412 nm (when measured in a non-coupled assay containing DTNB [Sigma No. D8130] alone as substrate) per minute at pH 7.0 at 25 °C.

Safety Information

• Storage Class: 12 - Non Combustible Liquids
• wgk: WGK 1
• flash_point_f: Not applicable
• flash_point_c: Not applicable
• ppe: Eyeshields, Gloves, multi-purpose combination respirator cartridge (US)