1OPR:
reference: The crystal structure of the orotate phosphoribosyltransferase complexed with orotate and alpha-D-5-phosphoribosyl-1-pyrophosphate., Scapin G, Ozturk DH, Grubmeyer C, Sacchettini JC, Biochemistry 1995 Aug 29;34(34):10744-54. PMID: 7545004

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