title: A Protonated Water Cluster as a Transient Proton-Loading Site in Cytochrome c Oxidase.
abstract: Cytochrome c oxidase (CcO) is a redox-driven proton pump that powers aerobic respiratory chains. We show here by multi-scale molecular simulations that a protonated water cluster near the active site is likely to serve as the transient proton-loading site (PLS) that stores a proton during the pumping process. The pKa of this water cluster is sensitive to the redox states of the enzyme, showing distinct similarities to other energy converting proton pumps.
authors.affiliation: Department Chemie, Technische Universität München (TUM), Lichtenbergstraße 4, 85747, Garching, Germany.
authors.forename: Shreyas
authors.initials: S
authors.lastname: Supekar
authors.affiliation: Department Chemie, Technische Universität München (TUM), Lichtenbergstraße 4, 85747, Garching, Germany.
authors.forename: Ana P
authors.initials: AP
authors.lastname: Gamiz-Hernandez
authors.affiliation: Department Chemie, Technische Universität München (TUM), Lichtenbergstraße 4, 85747, Garching, Germany. ville.kaila@ch.tum.de.
authors.forename: Ville R I
authors.initials: VR
authors.lastname: Kaila
mesh_terms: D000818:Animals; D020134:Catalytic Domain; D002417:Cattle; D004579:Electron Transport; D003576:Electron Transport Complex IV / Q000737:chemistry*; D056004:Molecular Dynamics Simulation; D010084:Oxidation-Reduction; D011522:Protons; D014867:Water / Q000737:chemistry*
chemical_list: D011522:Protons; D014867:Water; D003576:Electron Transport Complex IV
keywords: bioenergetics; electron transfer; enzymes; molecular dynamics; proton transfer