1OAO:
reference: Ni-Zn-[Fe4-S4] and Ni-Ni-[Fe4-S4] clusters in closed and open subunits of acetyl-CoA synthase/carbon monoxide dehydrogenase., Darnault C, Volbeda A, Kim EJ, Legrand P, Vernede X, Lindahl PA, Fontecilla-Camps JC, Nat Struct Biol 2003 Apr;10(4):271-9. PMID: 12627225

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