Rotary mechanism of the prokaryotic V o motor driven by proton motive force.

Autor: Kishikawa JI; Department of Molecular Biosciences, Kyoto Sangyo University, Kamigamo-Motoyama, Kita-ku, Kyoto, 603-8555, Japan.; Institute for Protein Research, Osaka University, 3-2 Yamadaoka, Suita, Osaka, 565-0871, Japan.; Department of Applied Biology, Kyoto Institute of Technology, Matsugasaki-Hashiuecho, Sakyo-ku, Kyoto, 606-8585, Japan., Nishida Y; Department of Molecular Biosciences, Kyoto Sangyo University, Kamigamo-Motoyama, Kita-ku, Kyoto, 603-8555, Japan., Nakano A; Department of Molecular Biosciences, Kyoto Sangyo University, Kamigamo-Motoyama, Kita-ku, Kyoto, 603-8555, Japan., Kato T; Institute for Protein Research, Osaka University, 3-2 Yamadaoka, Suita, Osaka, 565-0871, Japan., Mitsuoka K; Research Center for Ultra-High Voltage Electron Microscopy, Osaka University, Osaka, 567-0047, Japan., Okazaki KI; Research Center for Computational Science, Institute for Molecular Science, National Institutes of Natural Sciences, Okazaki, 444-8585, Japan. keokazaki@ims.ac.jp.; Graduate Institute for Advanced Studies, SOKENDAI, Okazaki, Aichi, 444-8585, Japan. keokazaki@ims.ac.jp., Yokoyama K; Department of Molecular Biosciences, Kyoto Sangyo University, Kamigamo-Motoyama, Kita-ku, Kyoto, 603-8555, Japan. yokoken@cc.kyoto-su.ac.jp.
Jazyk: angličtina
Zdroj: Nature communications [Nat Commun] 2024 Nov 20; Vol. 15 (1), pp. 9883. Date of Electronic Publication: 2024 Nov 20.
DOI: 10.1038/s41467-024-53504-x
Abstrakt: ATP synthases play a crucial role in energy production by utilizing the proton motive force (pmf) across the membrane to rotate their membrane-embedded rotor c-ring, and thus driving ATP synthesis in the hydrophilic catalytic hexamer. However, the mechanism of how pmf converts into c-ring rotation remains unclear. This study presents a 2.8 Å cryo-EM structure of the V o domain of V/A-ATPase from Thermus thermophilus, revealing precise orientations of glutamate (Glu) residues in the c 12 -ring. Three Glu residues face a water channel, with one forming a salt bridge with the Arginine in the stator (a/Arg). Molecular dynamics (MD) simulations show that protonation of specific Glu residues triggers unidirectional Brownian motion of the c 12 -ring towards ATP synthesis. When the key Glu remains unprotonated, the salt bridge persists, blocking rotation. These findings suggest that asymmetry in the protonation of c/Glu residues biases c 12 -ring movement, facilitating rotation and ATP synthesis.
Competing Interests: Competing interests: The authors declare no competing interests.
(© 2024. The Author(s).)
Databáze: MEDLINE
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