Mixed Atomistic and Coarse-Grained Molecular Dynamics:  Simulation of a Membrane-Bound Ion Channel

TitleMixed Atomistic and Coarse-Grained Molecular Dynamics:  Simulation of a Membrane-Bound Ion Channel
Publication TypeJournal Article
Year of Publication2006
AuthorsShi, Q, Izvekov, S, Voth, GA
JournalJ Phys Chem B
Volume110
Pagination15045-8
Keywords*Computer Simulation Dimyristoylphosphatidylcholine/chemistry Gramicidin/*chemistry Ion Channels/chemistry Lipid Bilayers/chemistry Models, Molecular Peptides/*chemistry Protein Conformation Quantum Theory Water/chemistry
Abstract

The recently developed multiscale coarse-graining (MS-CG) method (Izvekov, S.; Voth, G. A. J. Phys. Chem. B 2005, 109, 2469; J. Chem. Phys. 2005, 123, 134105) is used to build a mixed all-atom and coarse-grained (AA-CG) model of the gramicidin A (gA) ion channel embedded in a dimyristoylphosphatidylcholine (DMPC) lipid bilayer and water environment. In this model, the gA peptide was described in full atomistic detail, while the lipid and water molecules were described using coarse-grained representations. The atom-CG and CG-CG interactions in the mixed AA-CG model were determined using the MS-CG method. Molecular dynamics (MD) simulations were performed using the resulting AA-CG model. The results from simulations of the AA-CG model compare very favorably to those from all-atom MD simulations of the entire system. Since the MS-CG method employs a general and systematic approach to obtain effective interactions from the underlying all-atom models, the present approach to rigorously develop mixed AA-CG models has the potential to be extended to many other systems.

DOI10.1021/jp062700h