3CAV:
reference: The Crystal Structure of Human Delta4-3-Ketosteroid 5beta-Reductase Defines the Functional Role of the Residues of the Catalytic Tetrad in the Steroid Double Bond Reduction Mechanism., Faucher F, Cantin L, Luu-The V, Labrie F, Breton R, Biochemistry. 2008 Jul 15. PMID: 18624455

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