skip to main content


Title: Mechanistic insights into energy conservation by flavin-based electron bifurcation

The recently realized biochemical phenomenon of energy conservation through electron bifurcation provides biology with an elegant means to maximize utilization of metabolic energy. The mechanism of coordinated coupling of exergonic and endergonic oxidation-reduction reactions by a single enzyme complex has been elucidated through optical and paramagnetic spectroscopic studies revealing unprecedented features. Pairs of electrons are bifurcated over more than 1 volt of electrochemical potential by generating a low-potential, highly energetic, unstable flavin semiquinone and directing electron flow to an iron-sulfur cluster with a highly negative potential to overcome the barrier of the endergonic half reaction. As a result, the unprecedented range of thermodynamic driving force that is generated by flavin-based electron bifurcation accounts for unique chemical reactions that are catalyzed by these enzymes.
 [1] ;  [2] ;  [1] ;  [3] ;  [4] ;  [5] ;  [4] ;  [4] ;  [3] ;  [3] ;  [4] ;  [2] ; ORCiD logo [5] ; ORCiD logo [1] ;  [3] ;  [6]
  1. National Renewable Energy Lab. (NREL), Golden, CO (United States)
  2. Arizona State Univ., Tempe, AZ (United States)
  3. Univ. of Georgia, Athens, GA (United States)
  4. Montana State Univ., Bozeman, MT (United States)
  5. Univ. of Kentucky, Lexington, KY (United States)
  6. Montana State Univ., Bozeman, MT (United States); Washington State Univ., Pullman, WA (United States)
Publication Date:
Report Number(s):
Journal ID: ISSN 1552-4450
Grant/Contract Number:
Accepted Manuscript
Journal Name:
Nature Chemical Biology
Additional Journal Information:
Journal Volume: 13; Journal Issue: 6; Journal ID: ISSN 1552-4450
Nature Publishing Group
Research Org:
National Renewable Energy Lab. (NREL), Golden, CO (United States)
Sponsoring Org:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
Country of Publication:
United States
09 BIOMASS FUELS; 37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY; structural analysis; spectroscopy; electron bifurcation; flavoenzymes
OSTI Identifier: