1M57:
reference: The X-ray crystal structures of wild-type and EQ(I-286) mutant cytochrome c oxidases from Rhodobacter sphaeroides., Svensson-Ek M, Abramson J, Larsson G, Tornroth S, Brzezinski P, Iwata S, J Mol Biol 2002 Aug 9;321(2):329-39. PMID: 12144789

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