Electrostatics, hydration, and proton transfer dynamics in the membrane domain of respiratory complex I

• DOI: 10.1073/pnas.1319156111
• Publication Date: 2014-04-29T07:37:37Z
• Authors: Ville R. I. Kaila; Mårten Wikström; Gerhard Hummer
• Keywords: Models, Molecular; 0303 health sciences; Electron Transport Complex I; Escherichia coli Proteins; Membrane Proteins; Water; NADH Dehydrogenase; Molecular Dynamics Simulation; Protein Structure, Tertiary; Electron Transport; 03 medical and health sciences; Electrochemistry; Escherichia coli; Protons

Significance

Using large-scale classical and quantum simulations, we elucidate key aspects of the molecular function of complex I, a protein central to biological energy conversion. Complex I serves as the primary electron entry point into the mitochondrial and bacterial respiratory chains and operates as a redox-coupled proton pump. Our simulations suggest that transient water chains establish highly efficient pathways for proton transfer. Our findings form a basis for understanding long-range energy conversion in complex I, and mechanistic similarities to other redox-driven proton-pumps, such as cytochrome c oxidase and bacteriorhodopsin.