Acetyl-CoA synthase/CO dehydrogenase (ACS/CODH) is a bifunctional enzyme that catalyses the reversible reduction of CO2 to CO (CODH activity, the beta subunit) and the synthesis or degradation of acetyl-CoA (catalysed by ACS, the alpha subunit). CODH contains the B-, C-, and D-clusters. This domain represents the middle and C-terminal regions of CODH which have an alpha/beta Rossmann-like fold and are the contribute ligands to the active site C-cluster. The C-cluster generates CO from CO2 and contains one Ni atom, four Fe atoms, and five labile sulfur atoms, arranged as an asymmetrical heteronuclear [Ni-4Fe-5S] cluster [1,2,6,7].

1: A Ni-Fe-Cu center in a bifunctional carbon monoxide dehydrogenase/acetyl-CoA synthase. Doukov TI, Iverson TM, Seravalli J, Ragsdale SW, Drennan CL; Science. 2002;298:567-572. PMID:12386327

2: 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;10:271-279. PMID:12627225

3: A functional Ni-Ni-[4Fe-4S] cluster in the monomeric acetyl-CoA synthase from Carboxydothermus hydrogenoformans. Svetlitchnyi V, Dobbek H, Meyer-Klaucke W, Meins T, Thiele B, Romer P, Huber R, Meyer O; Proc Natl Acad Sci U S A. 2004;101:446-451. PMID:14699043

4: Novel domain arrangement in the crystal structure of a truncated acetyl-CoA synthase from Moorella thermoacetica. Volbeda A, Darnault C, Tan X, Lindahl PA, Fontecilla-Camps JC; Biochemistry. 2009;48:7916-7926. PMID:19650626

5: Crystallographic snapshots of cyanide- and water-bound C-clusters from bifunctional carbon monoxide dehydrogenase/acetyl-CoA synthase. Kung Y, Doukov TI, Seravalli J, Ragsdale SW, Drennan CL; Biochemistry. 2009;48:7432-7440. PMID:19583207

6: Crystal structure of a carbon monoxide dehydrogenase reveals a [Ni-4Fe-5S] cluster. Dobbek H, Svetlitchnyi V, Gremer L, Huber R, Meyer O; Science. 2001;293:1281-1285. PMID:11509720

7: Life on carbon monoxide: X-ray structure of Rhodospirillum rubrum Ni-Fe-S carbon monoxide dehydrogenase. Drennan CL, Heo J, Sintchak MD, Schreiter E, Ludden PW; Proc Natl Acad Sci U S A. 2001;98:11973-11978. PMID:11593006