3PKV:
reference: Toxoflavin Lyase Requires a Novel 1-His-2-Carboxylate Facial Triad., Fenwick MK, Philmus B, Begley TP, Ealick SE, Biochemistry. 2010 Dec 17. PMID: 21166463

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