1MRQ:
reference: Human 20alpha-hydroxysteroid dehydrogenase: crystallographic and site-directed mutagenesis studies lead to the identification of an alternative binding site for C21-steroids., Couture JF, Legrand P, Cantin L, Luu-The V, Labrie F, Breton R, J Mol Biol 2003 Aug 15;331(3):593-604. PMID: 12899831

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