Journal articles
On the Natural History of Flavin-Based Electron Bifurcation
Abstract : Electron bifurcation is here described as a special case of the continuum of electron transfer reactions accessible to two-electron redox compounds with redox cooperativity. We argue that electron bifurcation is foremost an electrochemical phenomenon based on (a) strongly inverted redox potentials of the individual redox transitions, (b) a high endergonicity of the first redox transition, and (c) an escapement-type mechanism rendering completion of the first electron transfer contingent on occurrence of the second one. This mechanism is proposed to govern both the traditional quinone-based and the newly discovered flavin-based versions of electron bifurcation. Conserved and variable aspects of the spatial arrangement of electron transfer partners in flavoenzymes are assayed by comparing the presently available 3D structures. A wide sample of flavoenzymes is analyzed with respect to conserved structural modules and three major structural groups are identified which serve as basic frames for the evolutionary construction of a plethora of flavin-containing redox enzymes. We argue that flavin-based and other types of electron bifurcation are of primordial importance to free energy conversion, the quintessential foundation of life, and discuss a plausible evolutionary ancestry of the mechanism.
Cited literature [95 references]
https://hal-amu.archives-ouvertes.fr/hal-01828959
Contributor : Laure Azzopardi <>
Submitted on : Thursday, July 5, 2018 - 5:38:18 PM
Last modification on : Tuesday, November 12, 2019 - 2:40:02 PM
Long-term archiving on: : Monday, October 1, 2018 - 6:45:45 PM
Contributor : Laure Azzopardi <>
Submitted on : Thursday, July 5, 2018 - 5:38:18 PM
Last modification on : Tuesday, November 12, 2019 - 2:40:02 PM
Long-term archiving on: : Monday, October 1, 2018 - 6:45:45 PM
File
fmicb-09-01357 2018.pdf
Publication funded by an institution