AKR1D1 human

AKR1D1 (aldo-keto reductase 1D1) is the only steroid 5β-reductase in humans. This enzyme shows major expression in liver and resides in cytoplasm. It is a member of the unique subfamily, AKR1D, of the aldo-keto reductase (AKR) superfamily, that are NAD(P)(H)-dependent oxidoreductases. AKR1D1 contains the characteristic (α/β)8 triosephosphate isomerase barrel in its core region, and has a molecular weight of 37kDa. Its C-terminal contains the active site residing on the β strands, and the ligand binding site is formed by long flexible loops.
Recombinant human AKR1D1 protein, fused to His-tag at N-terminus, was expressed in E.coli and purified by using conventional chromatography techniques.

AKR1D1 (aldo-keto reductase 1D1) catalyzes the reduction of Δ⁴-3-ketosteroids to 5β-dihydrosteroids in a stereospecific manner, and is responsible for inducing A/B cis-configuration of bile acids. It is a critical enzyme for steroid hormone metabolism (except estrogens) and bile acid biosynthesis. Mutations in this gene are linked with bile acid deficiency resulting in usually fatal neonatal hepatitis and cholestasis. Variants in this gene influence the expression of p450 enzymes, such as CYP3A4, CYP2C8, CYP2C9, CYP2C19, and CYP2B6, where up-regulation of AKR1D1 results in overexpression of these enzymes. Hence, this enzyme might indirectly be responsible for variation in drug metabolism or efficacy and adverse drug events in different individuals.

0.5 mg/mL in 20 mM Tris-HCl buffer (pH 8.0) containing 1 mM DTT, 100 mM NaCl and 20% glycerol.