EC Number   |
|---|
    2.3.1.169 | 49 kDa fragment containing residues 311-729 of the intact enzym. In the fragment, domains A2 and A3 have significantlymoved to each other, corresponding to a rotation around a hinge region located close to the C-terminus of the long interdomain helix |
| 2.3.1.169 | a 2.5 A resolution structure of xenon-pressurized CODH/ACS, examination of the nature of gaseous cavities within the enzyme. The cavity calculation program CAVENV accurately predicts the channels connecting the C- and A-clusters, with 17 of 19 xenon binding sites within the predicted regions. The enzyme has a channel for a small substrate, a channel plug, a flexible acetyl-CoA synthase subunit that can open to interact with a large substrate, and an interdomain cavity to putatively bind a medium-sized substrate |
| 2.3.1.169 | crystal structure of recombinant ACS lacking the N-terminal domain that interacts with carbon monoxide dehydrogenase 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 is most likely Cu or Zn. Incorporation of a functional Ni2Fe4S4 A-cluster would require only minor structural rearrangements |
| 2.3.1.169 | density functional theory and polarized continuum model study. The optimized geometries show a large structural variability of the A-cluster depending on the oxidation state and the ligand attached to the proximal nickel atom. The calculated pKa values and redox potentials are in favor of the two-electron reduction mechanism coupled to a proton transfer |
| 2.3.1.169 | sitting drop vapor diffusion at room temperature in a Coy anaerobic chamber, 0.005 ml of protein solution containing 40-60 mg/ml CODH/ACS in 50 mM Tris, pH 7.6, are mixed with 0.0075 ml of reservoir solution containing 8% polyethylene glycol MME 5000, 20% glycerol, 200 mM calcium acetate, 100 mM PIPES, pH 6.5, and 2 mM dithioerythritol, X-ray diffraction structure determination and analysis at 2.2 A resolution, multiwavelength anomalous dispersion techniques, molecular replacement |
| 2.3.1.169 | structures of the 310 kDa bifunctional CODH/acetyl-CoA synthase complex bound both with a substrate H2O/OH- molecule and with a cyanide inhibitor. Both in native crystals and identical crystals soaked in a solution containing potassium cyanide, the substrateH2O/OH- molecule exhibits binding to the unique Fe site of the C-cluster. Cyanide binding is also observed in a bent conformation to Ni of the C-cluster, adjacent the substrate H2O/OH-molecule. The bridging sulfide is not present in either structure. Findings do not support a fifth, bridging sulfide playing a catalytic role in the enzyme mechanism |
