3FYE:
reference: Redox-dependent conformational changes in cytochrome C oxidase suggest a gating mechanism for proton uptake., Qin L, Liu J, Mills DA, Proshlyakov DA, Hiser C, Ferguson-Miller S, Biochemistry. 2009 Jun 16;48(23):5121-30. PMID: 19397279

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