1QJG:
reference: Crystal structure of delta(5)-3-ketosteroid isomerase from Pseudomonas testosteroni in complex with equilenin settles the correct hydrogen bonding scheme for transition state stabilization., Cho HS, Ha NC, Choi G, Kim HJ, Lee D, Oh KS, Kim KS, Lee W, Choi KY, Oh BH, J Biol Chem. 1999 Nov 12;274(46):32863-8. PMID: 10551849

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