X-ray structures of catalytic intermediates of cytochrome c oxidase provide insights into its O2 activation and unidirectional proton-pump mechanisms
Atsuhiro Shimada, Yuki Etoh, Rika Kitoh-Fujisawa, Ai Sasaki, Kyoko Shinzawa‐Itoh, Takeshi Hiromoto, Eiki Yamashita, Kazumasa Muramoto, Tomitake Tsukihara, Shinya Yoshikawa
Abstract
state, preventing its detection, consistent with the unexpected Raman results. The H-pathway structures of both intermediates indicated that during proton-pumping from the hydrogen-bond network to the P-side, a transmembrane helix closes the water channel connecting the N-side with the hydrogen-bond network, facilitating unidirectional proton-pumping during the P-to-F transition.
Topics & Concepts
ChemistryCatalytic cycleProtonRaman spectroscopyCatalysisCytochrome c oxidasePhotochemistryMoleculeHydrogen bondCrystallographyStereochemistryEnzymePhysicsBiochemistryOpticsQuantum mechanicsOrganic chemistryPhotosynthetic Processes and MechanismsPhotoreceptor and optogenetics researchSpectroscopy and Quantum Chemical Studies