1Z9A:
reference: Probing the substrate binding site of Candida tenuis xylose reductase (AKR2B5) with site-directed mutagenesis., Kratzer R, Leitgeb S, Wilson DK, Nidetzky B, Biochem J. 2006 Jan 1;393(Pt 1):51-8. PMID: 16336198

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