Studies on the mechanism of electron bifurcation catalyzed by electron transferring flavoprotein (Etf) and butyryl-CoA dehydrogenase (Bcd) of acidaminococcus fermentans

Background: Flavin-based electron bifurcation explains the energy metabolism of anaerobic microorganisms. Results: Kinetic, structural, and spectral data revealed a detailed picture of the bifurcation process. Conclusion: NADH reduces β-FAD of Etf, which bifurcates one electron to Bcd via α-FAD and the other to ferredoxin. Repetition leads to reduction of crotonyl-CoA. Significance: The mechanism can be extended to other bifurcating systems. © 2014 by The American Society for Biochemistry and Molecular Biology, Inc.