Mechanically driven ATP synthesis by F1-ATPase

@article{Itoh2004MechanicallyDA,
  title={Mechanically driven ATP synthesis by F1-ATPase},
  author={Hiroyasu Itoh and Akira Takahashi and Kengo Adachi and Hiroyuki Noji and Ryohei Yasuda and Masasuke Yoshida and Kazuhiko Kinosita},
  journal={Nature},
  year={2004},
  volume={427},
  pages={465-468}
}
ATP, the main biological energy currency, is synthesized from ADP and inorganic phosphate by ATP synthase in an energy-requiring reaction. The F1 portion of ATP synthase, also known as F1-ATPase, functions as a rotary molecular motor: in vitro its γ-subunit rotates against the surrounding α3β3 subunits, hydrolysing ATP in three separate catalytic sites on the β-subunits. It is widely believed that reverse rotation of the γ-subunit, driven by proton flow through the associated Fo portion of ATP… 
Single molecule thermodynamics of ATP synthesis by F1-ATPase
TLDR
The amount of mechanical work exploited by the F1-motor to synthesize an ATP molecule during forced rotations is determined using a methodology combining a nonequilibrium theory and single molecule measurements of responses to external torque.
Phosphate release coupled to rotary motion of F1-ATPase
TLDR
Atomistic molecular dynamics simulations are used to construct a first atomistic conformation of the intermediate state following the 40° substep of rotary motion, and to study the timing and molecular mechanism of inorganic phosphate (Pi) release coupled to the rotation.
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TLDR
Direct evidence is provided that F1 is designed to tightly couple its catalytic reactions with the mechanical rotation, and it is suggested that the ɛ-subunit has an essential function during ATP synthesis.
Thermodynamic efficiency and mechanochemical coupling of F1-ATPase
TLDR
It is found that the maximum work performed by F1-ATPase per 120° step is nearly equal to the thermodynamical maximum work that can be extracted from a single ATP hydrolysis under a broad range of conditions.
Simple mechanism whereby the F1-ATPase motor rotates with near-perfect chemomechanical energy conversion
TLDR
The force for rotation (torque) under various ΔGATP conditions as a function of rotation angles of the γ subunit with quasi-static, single-molecule manipulation and estimated mechanical work from the area of the function is measured.
How subunit coupling produces the γ-subunit rotary motion in F1-ATPase
  • J. Pu, M. Karplus
  • Biology
    Proceedings of the National Academy of Sciences
  • 2008
TLDR
A coarse-grained plastic network model is used to show at a residue level of detail how the conformational changes of the catalytic β-subunits act on the γ-subunit through repulsive van der Waals interactions to generate a torque that drives unidirectional rotation, as observed experimentally.
Trapping the ATP binding state leads to a detailed understanding of the F1-ATPase mechanism
TLDR
An atomic-level model of the coupling between ATP hydrolysis and γ-subunit rotation is developed, and a rationalization of how F1-ATPase achieves the coupling Between the small changes in the active site of βDP and the 40° rotation of γ is provided.
F1 rotary motor of ATP synthase is driven by the torsionally-asymmetric drive shaft
TLDR
The motor efficiency is discussed, which is very low if calculated from the useful mechanical work it produces - but is quite high when the ‘useful outcome’ is measured in the number of H+ pushed against the chemical gradient.
ATP Synthesis, Chemistry of
TLDR
This specialized topics review summarizes the current understanding of the biological process of ATP synthesis and emphasizes recent insights into the atomic structure of ATP synthase and the fascinating mechanism of subunit-rotation-induced energy coupling.
Controlled rotation of the F1-ATPase reveals differential and continuous binding changes for ATP synthesis
TLDR
It is shown that the rates do not significantly depend on the rotary direction, indicating ATP synthesis by direct reversal of the hydrolysis-driven rotation, indicating tight coupling between the rotor angle and site affinities.
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References

SHOWING 1-10 OF 38 REFERENCES
Energy transduction in the F1 motor of ATP synthase
TLDR
It is concluded that the F1 motor achieves its high mechanical torque and almost 100% efficiency because it converts the free energy of ATP binding into elastic strain, which is then released by a coordinated kinetic and tightly coupled conformational mechanism to create a rotary torque.
Direct observation of the rotation of F1-ATPase
TLDR
It is shown that a single molecule of F1-ATPase acts as a rotary motor, the smallest known, by direct observation of its motion by attaching a fluorescent actin filament to the γ-subunit as a marker, which enabled us to observe this motion directly.
Resolution of distinct rotational substeps by submillisecond kinetic analysis of F1-ATPase
TLDR
It is shown by high-speed imaging that the 120° step consists of roughly 90° and 30° substeps, each taking only a fraction of a millisecond, which supports the binding-change model for ATP synthesis by reverse rotation of F1-ATPase.
H+/ATP ratio of proton transport‐coupled ATP synthesis and hydrolysis catalysed by CF0F1—liposomes
The H+/ATP ratio and the standard Gibbs free energy of ATP synthesis were determined with a new method using a chemiosmotic model system. The purified H+‐translocating ATP synthase from chloroplasts
A rotary molecular motor that can work at near 100% efficiency.
TLDR
In vitro, it is confirmed in vitro that F1 indeed does ca.
Effect of dimethylsulfoxide on ATP synthesis by mitochondrial soluble F1-ATPase.
  • J. Sakamoto
  • Chemistry, Biology
    Journal of biochemistry
  • 1984
TLDR
It is suggested that DMSO increases the affinity of F1 and Pi and shifts the equilibrium from the enzyme-ADP-Pi complex to the enzymes-ATP complex during the ATP synthesis.
The ATP synthase--a splendid molecular machine.
  • P. Boyer
  • Chemistry
    Annual review of biochemistry
  • 1997
An X-ray structure of the F1 portion of the mitochondrial ATP synthase shows asymmetry and differences in nucleotide binding of the catalytic beta subunits that support the binding change mechanism
The reversal of the myosin and actomyosin ATPase reactions and the free energy of ATP binding to myosin.
Subunit rotation in Escherichia coli FoF1-ATP synthase during oxidative phosphorylation.
TLDR
F1 is established as the second example in nature where proton transport is coupled to subunit rotation, and a brief exposure to conditions for ATP synthesis followed by reoxidation resulted in a significant amount of betaflag appearing in the beta-gamma crosslinked product.
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