5UB9:
reference: A dimeric catalytic core relates the short and long forms of ATP-phosphoribosyltransferase., Mittelstadt G, Jiao W, Livingstone E, Moggre GJ, Nazmi AR, Parker EJ, Biochem J. 2017 Dec 5. pii: BCJ20170762. doi: 10.1042/BCJ20170762. PMID: 29208762

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