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Bio-layer Interferometry for Measuring Kinetics of Protein-protein Interactions and Allosteric Ligand Effects
Published on: February 18, 2014
Absolute FKBP binding affinities obtained via nonequilibrium unbinding simulations
1Department of Physics, University of Idaho, Moscow, Idaho 83844-0903, USA. ytreberg@uidaho.edu
The Journal of Chemical Physics
|May 2, 2009
Summary
Nonequilibrium simulations offer a straightforward method for estimating protein-ligand binding affinities. Using the stiff-spring approximation with the second cumulant expansion improves accuracy for these simulations.
Area of Science:
- Computational chemistry and molecular dynamics.
- Biophysics and structural biology.
Background:
- Accurate protein-ligand binding affinity calculation is crucial for drug discovery.
- Existing equilibrium methods can be computationally intensive.
- Nonequilibrium methods offer a potentially simpler alternative.
Purpose of the Study:
- To compute absolute binding affinities for ligands bound to the FKBP protein.
- To evaluate the accuracy of nonequilibrium unbinding simulations.
- To compare nonequilibrium results with equilibrium methods and experimental data.
Main Methods:
- Utilized nonequilibrium unbinding simulations to calculate binding affinities.
- Employed a straightforward methodology adaptable to standard molecular simulation packages.
- Compared results against fully equilibrium approaches and experimental data.
Main Results:
- Nonequilibrium simulations provided estimates of protein-ligand binding affinities.
- The stiff-spring approximation combined with the second cumulant expansion yielded accurate results.
- The physical pathway approach avoided complex alchemical decoupling schemes.
Conclusions:
- Nonequilibrium simulations present a simple and effective approach for estimating protein-ligand binding affinities.
- Specific methodological choices (stiff-spring approximation, second cumulant expansion) are key for accuracy.
- This method could streamline the process of drug discovery by providing rapid affinity estimations.
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