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Updated: Jul 24, 2026
10:39
Visualization of ATP Synthase Dimers in Mitochondria by Electron Cryo-tomography
Published on: September 14, 2014
Toward an adequate scheme for the ATP synthase catalysis
1Molecular Biology Institute, Boyer Hall, University of California, Los Angeles, CA 90095-1570, USA. pdboyer@ucla.edu
Biochemistry. Biokhimiia
|December 12, 2001
Summary
Evidence strongly favors bi-site activation for ATP synthase catalysis, suggesting nucleotide binding at a second site. Three catalytic site types are proposed, with conformational changes driving ATP synthesis and hydrolysis.
Area of Science:
- Biochemistry
- Enzyme kinetics
- Molecular biology
Background:
- ATP synthase is a crucial enzyme for cellular energy production.
- Understanding its catalytic mechanism is key to comprehending energy transduction.
- Previous models proposed different nucleotide binding mechanisms.
Purpose of the Study:
- To review and revise the proposed reaction sequence for ATP synthase catalysis.
- To evaluate evidence for bi-site versus tri-site activation during ATP hydrolysis.
- To correlate conformational changes in ATP synthase with general enzyme catalysis.
Main Methods:
- Review of existing experimental data and literature.
- Analysis of X-ray crystallographic structures of ATP synthase.
- Comparison of proposed mechanisms with general enzyme catalysis principles.
Main Results:
- Evidence strongly supports bi-site activation over tri-site activation for rapid ATP hydrolysis.
- A revised reaction sequence is proposed, involving three types of catalytic sites.
- Conformational changes, including site interconversions during a 120-degree rotation, are central to the mechanism.
Conclusions:
- The revised model accounts for nucleotide binding and release during ATP synthesis and hydrolysis.
- The enzyme's catalytic cycle involves distinct site conformations and interconversions.
- Proposed mechanisms align with broader principles of enzyme catalysis.
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