2X0H:
reference: Visualizing the Reaction Coordinate of an O-GlcNAc Hydrolase., He Y, Macauley MS, Stubbs KA, Vocadlo DJ, Davies GJ, J Am Chem Soc. 2010 Jan 12. PMID: 20067256

This OCA Structure page
uses Jmol, developed by the Jmol Development Team (documentation).