2VR0:
reference: Quinol oxidation by c-type cytochromes: structural characterization of the menaquinol binding site of NrfHA., Rodrigues ML, Scott KA, Sansom MS, Pereira IA, Archer M, J Mol Biol. 2008 Aug 29;381(2):341-50. Epub 2008 Jun 3. PMID: 18597779

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