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Multidimensional potentials of mean force from biased experiments along a single coordinate.
1Department of Chemistry, University of California at San Diego, San Diego, California 92093, USA. dminh@mccammon.ucsd.edu
The Journal of Physical Chemistry. B
|April 5, 2007
Summary
This study introduces a new method for multidimensional potential of mean force (PMF) reconstruction from nonequilibrium single-molecule pulling experiments. This approach proves more efficient than traditional methods for enhanced sampling in complex systems.
Area of Science:
- Computational Chemistry
- Statistical Mechanics
- Biophysics
Background:
- External biasing forces are used to improve sampling in rare phase space regions.
- Typically, these experiments aim to calculate one-dimensional potentials of mean force (PMF).
Purpose of the Study:
- To develop a method for constructing multidimensional PMFs along arbitrary degrees of freedom.
- To compare the efficiency of this new protocol against existing methods.
Main Methods:
- A novel protocol for multidimensional PMF reconstruction from nonequilibrium single-molecule pulling experiments.
- Testing on two-dimensional potential surfaces with varying correlation levels.
- Comparison with equilibrium umbrella sampling and free diffusion methods.
Main Results:
- The developed protocol successfully reconstructs multidimensional PMFs.
- Nonequilibrium pulling was found to be the most efficient method for reconstruction and convergence.
- Source code for the analysis is made freely available.
Conclusions:
- Multidimensional PMF reconstruction is feasible from nonequilibrium pulling experiments.
- This method offers enhanced efficiency for complex systems compared to traditional approaches.
- The open-source code facilitates wider adoption and research in the field.
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