Mechanistic insights into energy conservation by flavin-based electron bifurcation [electronic resource]

• Ngôn ngữ: eng
• Ký hiệu phân loại: 666.5 Porcelain
• Thông tin xuất bản: Washington, D.C. : Oak Ridge, Tenn. : United States. Dept. of Energy. Office of Science ; Distributed by the Office of Scientific and Technical Information, U.S. Dept. of Energy, 2017
• Mô tả vật lý: Size: p. 655-659 : , digital, PDF file.
• Bộ sưu tập: Metadata
• ID: 263260
• Chủ đề: 1. 09 biomass fuels; 2. 37 inorganic, organic, physical, and analytical chemistry; 3. Electron bifurcation; 4. Spectroscopy; 5. Structural analysis

Tóm tắt

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.