2PAK:
reference: The X-ray Structure of dTDP-4-Keto-6-deoxy-D-glucose-3,4-ketoisomerase., Davis ML, Thoden JB, Holden HM, J Biol Chem. 2007 Jun 29;282(26):19227-36. Epub 2007 Apr 25. PMID: 17459872

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