4YIW:
reference: Ca-asp bound X-ray structure and inhibition of Bacillus anthracis dihydroorotase (DHOase)., Rice AJ, Lei H, Santarsiero BD, Lee H, Johnson ME, Bioorg Med Chem. 2016 Oct 1;24(19):4536-43. doi: 10.1016/j.bmc.2016.07.055. Epub , 2016 Jul 29. PMID: 27499369

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