## Abstract Computer simulations offer a valuable way to study membrane systems, from simple lipid bilayers to large transmembrane protein complexes and lipid‐nucleic acid complexes for drug delivery. Their accuracy depends on the quality of the force field parameters used to describe the component
Modification of the CHARMM force field for DMPC lipid bilayer
✍ Scribed by Carl-Johan Högberg; Alexei M. Nikitin; Alexander P. Lyubartsev
- Publisher
- John Wiley and Sons
- Year
- 2008
- Tongue
- English
- Weight
- 897 KB
- Volume
- 29
- Category
- Article
- ISSN
- 0192-8651
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✦ Synopsis
Abstract
The CHARMM force field for DMPC lipids was modified in order to improve agreement with experiment for a number of important properties of hydrated lipid bilayer. The modification consists in introduction of a scaling factor 0.83 for 1–4 electrostatic interactions (between atoms separated by three covalent bonds), which provides correct transgauche ratio in the alkane tails, and recalculation of the headgroup charges on the basis of HF/6‐311(d,p) ab‐initio computations. Both rigid TIP3P and flexible SPC water models were used with the new lipid model, showing similar results. The new model in a 75 ns simulation has shown a correct value of the area per lipid at zero surface tension, as well as good agreement with the experiment for the electron density, structure factor, and order parameters, including those in the headgroup part of lipids. © 2008 Wiley Periodicals, Inc. J Comput Chem, 2008
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