1M53:
reference: Isomaltulose synthase (PalI) of Klebsiella sp. LX3. Crystal structure and implication of mechanism., Zhang D, Li N, Lok SM, Zhang LH, Swaminathan K, J Biol Chem 2003 Sep 12;278(37):35428-34. Epub 2003 Jun 20. PMID: 12819210

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