4FRF:
reference: Structural studies and protein engineering of inositol phosphate multikinase., Endo-Streeter S, Tsui MK, Odom AR, Block J, York JD, J Biol Chem. 2012 Oct 12;287(42):35360-9. doi: 10.1074/jbc.M112.365031. Epub 2012, Aug 15. PMID: 22896696

This OCA Structure page
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