2009/07/22 by Anatoly Yu. Smirnov, Sergey Savel’ev, Sergey E. Savel'ev +1
Biochemistry, Genetics and Molecular Biology · Chemistry · Neuroscience · Physics and Astronomy · #ATP synthase #Biochemistry #Biophysics #Chemical physics #Chemiosmosis #Chemistry #Coupling (piping) #Diffusion #Electrochemical gradient #Electron #Electron transport chain #Inorganic chemistry #Materials science #Membrane #Nuclear physics #Photoreceptor and optogenetics research #Photosynthetic Processes and Mechanisms #Physics #Proton #Proton transport #Redox #Spectroscopy and Quantum Chemical Studies #Thermodynamics #cond-mat.soft #physics.bio-ph #q-bio.SC
paper · pdf · doi:10.1103/physreve.80.011916
published as Phys. Rev. E 80, 011916 (2009) · 26 pages, 4 figures. A similar model is used in arXiv:0806.3233 for a different biological system. Minor changes in the Acknowledgements section
openalex publication_date 2009/07/22 · arxiv created 2009/12/04 · arxiv updated 2015/05/13 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
Respiration in bacteria involves a sequence of energetically coupled electron and proton transfers creating an electrochemical gradient of protons (a proton-motive force) across the inner bacterial membrane. With a simple kinetic model, we analyze a redox loop mechanism of proton-motive force generation mediated by a molecular shuttle diffusing inside the membrane. This model, which includes six electron-binding and two proton-binding sites, reflects the main features of nitrate respiration in E. coli bacteria. We describe the time evolution of the proton translocation process. We find that the electron-proton electrostatic coupling on the shuttle plays a significant role in the process of energy conversion between electron and proton components. We determine the conditions where the redox loop mechanism is able to translocate protons against the transmembrane voltage gradient above 200 mV with a thermodynamic efficiency of about 37%, in the physiologically important range of temperatures from 250 to 350 K.