An averaged polarizable potential for multiscale modeling in phospholipid membranes
Sarah Witzke1, Nanna Holmgaard List2, Jógvan Magnus Haugaard Olsen1
1Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, Odense M, DK-5230, Denmark.
Journal of Computational Chemistry
|February 5, 2017
Summary
New polarizable parameters are essential for accurate computational studies of lipid membranes. Standard non-polarizable force fields suffice for smaller-scale lipid simulations.
Area of Science:
- Computational chemistry
- Molecular dynamics
- Biophysics
Background:
- Phospholipids are key components of biological membranes.
- Accurate molecular modeling requires precise representation of atomic properties.
- Polarizable force fields are crucial for describing electronic response in molecular systems.
Purpose of the Study:
- To develop average atom-centered charges and polarizabilities for common phospholipids.
- To assess the necessity of polarizable parameters for lipid embedding calculations.
- To evaluate the performance of polarizable versus non-polarizable models for membrane simulations.
Main Methods:
- Development of average atom-centered charges and polarizabilities.
- Polarizable embedding calculations.
- Investigation of three specific phospholipids: DMPC, POPC, and POPS.
- Conformational analysis of lipid molecules.
Main Results:
- Developed polarizable parameters for DMPC, POPC, and POPS.
- Observed strong dependence of charges and polarizabilities on lipid conformation.
- Highlighted the importance of explicit polarization for membrane simulations.
- Demonstrated that non-polarizable force fields are adequate for structural and dynamical studies of smaller lipid assemblies.
Conclusions:
- Specially developed polarizable parameters are required for accurate embedding calculations in lipid membranes.
- Non-polarizable point-charge force fields are sufficient for structural and dynamical studies of isolated lipids or smaller assemblies.
- The findings guide the selection of appropriate computational models for different lipid simulation scales.
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