Novel domain arrangement in the crystal structure of a truncated acetyl-CoA synthase from Moorella thermoacetica. Academic Article uri icon


  • Ni-dependent acetyl-CoA synthase (ACS) and CO dehydrogenase (CODH) constitute the central enzyme complex of the Wood-Ljungdahl pathway of acetyl-CoA formation. The crystal structure of a recombinant bacterial ACS lacking the N-terminal domain that interacts with CODH shows a large reorganization of the remaining two globular domains, producing a narrow cleft of suitable size, shape, and nature to bind CoA. Sequence comparisons with homologous archaeal enzymes that naturally lack the N-terminal domain show that many amino acids lining this cleft are conserved. Besides the typical [4Fe-4S] center, the A-cluster contains only one proximal metal ion that, according to anomalous scattering data, is most likely Cu or Zn. Incorporation of a functional Ni(2)Fe(4)S(4) A-cluster would require only minor structural rearrangements. Using available structures, a plausible model of the interaction between CODH and the smaller ACS in archaeal multienzyme complexes is presented, along with a discussion of evolutionary relationships of the archaeal and bacterial enzymes.

published proceedings

  • Biochemistry

author list (cited authors)

  • Volbeda, A., Darnault, C., Tan, X., Lindahl, P. A., & Fontecilla-Camps, J. C.

citation count

  • 12

complete list of authors

  • Volbeda, Anne||Darnault, Claudine||Tan, Xiangshi||Lindahl, Paul A||Fontecilla-Camps, Juan C

publication date

  • August 2009