3VNI:
reference: Crystal structures of D-psicose 3-epimerase from Clostridium cellulolyticum H10 and its complex with ketohexose sugars., Chan HC, Zhu Y, Hu Y, Ko TP, Huang CH, Ren F, Chen CC, Ma Y, Guo RT, Sun Y, Protein Cell. 2012 Feb;3(2):123-31. Epub 2012 Mar 17. PMID: 22426981

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