Structural and electron paramagnetic resonance (EPR) studies of mononuclear molybdenum enzymes from sulfate-reducing bacteria

Acc Chem Res. 2006 Oct;39(10):788-96. doi: 10.1021/ar050104k.


Molybdenum and tungsten are found in biological systems in a mononuclear form in the active site of a diverse group of enzymes that generally catalyze oxygen-atom-transfer reactions. The metal atom (Mo or W) is coordinated to one or two pyranopterin molecules and to a variable number of ligands such as oxygen (oxo, hydroxo, water, serine, aspartic acid), sulfur (cysteines), and selenium (selenocysteines) atoms. In addition, these proteins contain redox cofactors such as iron-sulfur clusters and heme groups. All of these metal cofactors are along an electron-transfer pathway that mediates the electron exchange between substrate and an external electron acceptor (for oxidative reactions) or donor (for reductive reactions). We describe in this Account a combination of structural and electronic paramagnetic resonance studies that were used to reveal distinct aspects of these enzymes.

Publication types

  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Aldehyde Oxidoreductases / genetics
  • Aldehyde Oxidoreductases / metabolism
  • Bacteria / enzymology*
  • Binding Sites
  • Electron Spin Resonance Spectroscopy
  • Enzyme Inhibitors / chemistry
  • Enzyme Inhibitors / pharmacology
  • Enzymes / chemistry*
  • Enzymes / genetics
  • Formate Dehydrogenases / genetics
  • Formate Dehydrogenases / metabolism
  • Models, Molecular
  • Molybdenum / chemistry*
  • Stereoisomerism
  • Sulfates / metabolism*


  • Enzyme Inhibitors
  • Enzymes
  • Sulfates
  • Molybdenum
  • Formate Dehydrogenases
  • Aldehyde Oxidoreductases