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Dynamical fluctuations in biochemical reactions and cycles
S Pressé1, K Ghosh, R Phillips
1Department of Pharmaceutical Chemistry, University of California, San Francisco, California 94158, USA.
Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics
|January 15, 2011
Summary
We developed a new theory for biochemical reactions using maximum caliber. This method helps interpret experiments and quantifies how cycle size and driving force affect noise and backward spin in biological systems.
Area of Science:
- Biochemistry
- Chemical Kinetics
- Statistical Mechanics
Background:
- Biochemical reactions often involve complex dynamics and fluctuations.
- Understanding these processes is crucial for molecular motors, enzymes, and biological clocks.
- Interpreting single-molecule and few-particle experiments presents unique challenges.
Purpose of the Study:
- To develop a theoretical framework for analyzing dynamics and fluctuations in cyclic and linear biochemical reactions.
- To provide a method for interpreting experimental data from few-particle biochemical systems.
- To quantify the relationship between system parameters and reaction noise.
Main Methods:
- Utilized the maximum caliber approach to compute the ensemble of system paths.
- Focused on biochemical cycles where all states are observable.
- Developed a method to estimate small-number features from experimental data.
Main Results:
- Noise in biochemical cycles increases with cycle size.
- Noise decreases with the driving force of the cycle.
- Developed a recipe for estimating backward spin probability, which diminishes exponentially with deviation from equilibrium.
Conclusions:
- The maximum caliber approach offers a powerful tool for studying nonequilibrium biochemical systems.
- The findings provide insights into noise and fluctuations in observable biochemical cycles.
- This method has potential applications in interpreting single-molecule experiments and understanding biological clocks.
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