title: Characterization and spectroscopic properties of reduced Mo and W formate dehydrogenase from C. thermoaceticum.
abstract: Formate dehydrogenase (FDH) (EC 1.2.1.43) from C. thermoaceticum has been purified in two forms. One contains tungsten (W), and the other is enriched in molybdenum (Mo). The W-FDH is clearly active, while the Mo results are ambiguous with enzymatic activities generally lower in the Mo-enriched samples. Spectroscopic studies (EPR, absorption, and CD) on W-FDH and Mo-FDH demonstrate that no signal correlates to the group VI metal active site in the dithionite-reduced enzyme. This lack of a W(V) EPR signal is in contrast to the results observed for tungsten-substituted sulfite oxidase which is inactive.
mesh_terms: D000445:Aldehyde Oxidoreductases / Q000378:metabolism*; D001665:Binding Sites; D002942:Circular Dichroism; D003013:Clostridium / Q000201:enzymology*; D004578:Electron Spin Resonance Spectroscopy; D004789:Enzyme Activation; D005560:Formate Dehydrogenases / Q000378:metabolism*; D007700:Kinetics; D008982:Molybdenum / Q000032:analysis; D011487:Protein Conformation; D013053:Spectrophotometry; D014414:Tungsten / Q000032:analysis
chemical_list: D008982:Molybdenum; D005560:Formate Dehydrogenases; D000445:Aldehyde Oxidoreductases; D014414:Tungsten