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Rotary ATPases are molecular rotary motors involved in biological energy conversion. They either synthesize or hydrolyze the universal biological energy carrier adenosine triphosphate. Recent work has elucidated the general architecture and subunit compositions of all three sub-types of rotary ATPases. Composite models of the intact F-, V- and A-type ATPases have been constructed by fitting high-resolution X-ray structures of individual subunits or sub-complexes into low-resolution electron densities of the intact enzymes derived from electron cryo-microscopy. Electron cryo-tomography has provided new insights into the supra-molecular arrangement of eukaryotic ATP synthases within mitochondria and mass-spectrometry has started to identify specifically bound lipids presumed to be essential for function. Taken together these molecular snapshots show that nano-scale rotary engines have much in common with basic design principles of man made machines from the function of individual "machine elements" to the requirement of the right "fuel" and "oil" for different types of motors.
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http://dx.doi.org/10.4161/bioa.23301 | DOI Listing |
Annu Rev Biophys
May 2025
Department of Structural Biology, Max Planck Institute of Biophysics, Frankfurt am Main, Germany; email:
Cryo-electron microscopy (cryo-EM) is the method of choice for investigating the structures of membrane protein complexes at high resolution under near-native conditions. This review focuses on recent cryo-EM work on mitochondrial complex I and ATP synthase. Single-particle cryo-EM structures of complex I from mammals, plants, and fungi extending to a resolution of 2 Å show different functional states, indicating consistent conformational changes of loops near the Q binding site, clusters of internal water molecules in the membrane arm, and an α-π transition in a membrane-spanning helix that opens and closes the proton transfer path.
View Article and Find Full Text PDFNat Commun
April 2025
Program in Molecular Medicine, Peter Gilgan Center for Research and Learning, The Hospital for Sick Children, Toronto, ON, Canada.
The type IV pilus family uses PilT/VirB11-like ATPases to rapidly assemble and disassemble pilin subunits. Among these, the tight adherence (Tad) pilus performs both functions using a single bifunctional ATPase, CpaF. Here, we determine three conformationally distinct structures of CpaF hexamers with varying nucleotide occupancies by cryo-electron microscopy.
View Article and Find Full Text PDFBiomolecules
March 2025
Artie McFerrin Department of Chemical Engineering, Texas A&M University, College Station, TX 77480, USA.
The bacterial flagellar motor is one of the few known rotary motors, powering motility and chemotaxis. The mechanisms underlying its rotation and the switching of its rotational direction are fundamental problems in biology that are of significant interest. Recent high-resolution studies of the flagellar motor have transformed our understanding of the motor, revealing a novel gear mechanism where a membranous pentamer of MotA proteins rotates around a cell wall-anchored dimer of MotB proteins to turn the contacting flagellar rotor.
View Article and Find Full Text PDFJ Biol Chem
April 2025
Institute for Molecular Sciences, National Institutes of Natural Sciences, Okazaki, Aichi, Japan; Graduate Institute for Advanced Studies, SOKENDAI, Kanazawa, Japan. Electronic address:
V-ATPases generally function as ion pumps driven by ATP hydrolysis in the cell, but their capability of ATP synthesis remains largely unexplored. Here we show ATP synthesis of Na-transporting Enterococcus hirae V-ATPase (EhVV) driven by the electrochemical potential gradient of Na across the membrane (sodium motive force, smf). We reconstituted EhVV into liposome and performed a luciferin/luciferase-based assay to analyze ATP synthesis quantitatively.
View Article and Find Full Text PDFPhys Rev E
February 2025
Graduate School of China Academy of Engineering Physics, Beijing 100193, China.
Chemical gradients provide the primordial energy for biological functions by driving the mechanical movement of microscopic engines. Their thermodynamic properties remain elusive, especially concerning the dynamic change in energy demand in biological systems. In this article, we derive a constraint relation between the output power and the conversion efficiency for a chemically fueled steady-state rotary motor analogous to the F_{0} motor of ATPase.
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