2KMY:
reference: Redox linked conformational changes in cytochrome c3 from Desulfovibrio desulfuricans ATCC 27774., Paixao VB, Vis H, Turner DL, Biochemistry. 2010 Nov 9;49(44):9620-9. PMID: 20886839

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