4GZ6:
reference: Structural snapshots of the reaction coordinate for O-GlcNAc transferase., Lazarus MB, Jiang J, Gloster TM, Zandberg WF, Whitworth GE, Vocadlo DJ, Walker S, Nat Chem Biol. 2012 Dec;8(12):966-8. doi: 10.1038/nchembio.1109. Epub 2012 Oct, 28. PMID: 23103939

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