Mouse 3(17)
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-hydroxysteroid dehydrogenase (AKR1C21) is a member of the aldo-keto reductase superfamily that catalyses the oxido-reduction of steroid hormones such as estrogens, androgens and neurosteroids. Inhibitors of aldose reductase (AR), a member of the same superfamily, were evaluated against AKR1C21. Models of the enzyme–inhibitor complexes suggest that Tyr118 and Phe311 are important residues for inhibitor recognition and orientation in the active site of AKR1C21.