The active species of 'CO2' utilized by formylmethanofuran dehydrogenase from methanogenic Archaea

Eur J Biochem. 1997 Sep 15;248(3):919-24. doi: 10.1111/j.1432-1033.1997.00919.x.


Formylmethanofuran dehydrogenase from methanogenic Archaea catalyzes the reversible conversion of CO2 and methanofuran to formylmethanofuran, which is an intermediate in methanogenesis from CO2, a biological process yielding approximately 0.3 billion tons of CH4 per year. With the enzyme from Methanosarcina barkeri, it is shown that CO2 rather than HCO3- is the active species of 'CO2' utilized by the dehydrogenase. Evidence is also presented that the enzyme catalyzes a methanofuran-dependent exchange between CO2 and the formyl group of formylmethanofuran. The results are consistent with N-carboxymethanofuran being an intermediate in CO2 reduction to formylmethanofuran.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aldehyde Oxidoreductases / metabolism*
  • Bicarbonates / metabolism
  • Carbon Dioxide / metabolism*
  • Carbon Radioisotopes
  • Furans / metabolism
  • Kinetics
  • Methanosarcina barkeri / enzymology*
  • Methanosarcina barkeri / metabolism
  • Molecular Structure
  • Temperature


  • Bicarbonates
  • Carbon Radioisotopes
  • Furans
  • Carbon Dioxide
  • carbon dioxide reduction factor
  • formylmethanofuran
  • Aldehyde Oxidoreductases
  • formylmethanofuran dehydrogenase