title: An improved united atom force field for simulation of mixed lipid bilayers.
abstract: We introduce a new force field (43A1-S3) for simulation of membranes by the Gromacs simulation package. Construction of the force fields is by standard methods of electronic structure computations for bond parameters and charge distribution and specific volumes and heats of vaporization for small-molecule components of the larger lipid molecules for van der Waals parameters. Some parameters from the earlier 43A1 force field are found to be correct in the context of these calculations, while others are modified. The validity of the force fields is demonstrated by correct replication of X-ray form factors and NMR order parameters over a wide range of membrane compositions in semi-isotropic NTP 1 atm simulations. 43-A1-S3 compares favorably with other force fields used in conjunction with the Gromacs simulation package with respect to the breadth of phenomena that it accurately reproduces.
authors.affiliation: Department of Molecular and Integrative Physiology, National Center for Supercomputing Applications, University of Illinois, Urbana, Illinois 61801, USA.
authors.forename: See-Wing
authors.initials: SW
authors.lastname: Chiu
authors.forename: Sagar A
authors.initials: SA
authors.lastname: Pandit
authors.forename: H L
authors.initials: HL
authors.lastname: Scott
authors.forename: Eric
authors.initials: E
authors.lastname: Jakobsson
mesh_terms: D015060:1,2-Dipalmitoylphosphatidylcholine / Q000737:chemistry; D000465:Algorithms; D002627:Chemistry, Physical / Q000379:methods; D003198:Computer Simulation; D004134:Dimyristoylphosphatidylcholine / Q000737:chemistry; D004952:Esters / Q000737:chemistry; D008051:Lipid Bilayers / Q000737:chemistry*; D008055:Lipids / Q000737:chemistry; D009682:Magnetic Resonance Spectroscopy; D008956:Models, Chemical; D015233:Models, Statistical; D008962:Models, Theoretical; D008968:Molecular Conformation; D015203:Reproducibility of Results; D014965:X-Rays
chemical_list: D004952:Esters; D008051:Lipid Bilayers; D008055:Lipids; D015060:1,2-Dipalmitoylphosphatidylcholine; D004134:Dimyristoylphosphatidylcholine