An implicit solvent coarse-grained lipid model with correct stress profile.
We develop a coarse-grained parametrization strategy for lipid membranes that we illustrate for a dipalmitoylphosphatidylcholine bilayer. Our coarse-graining approach eliminates the high cost of explicit solvent but maintains more lipid interaction sites. We use a broad attractive tail-tail potential and extract realistic bonded potentials of mean force from all-atom simulations, resulting in a model with a sharp gel to fluid transition, a correct bending modulus, and overall very reasonable dynamics when compared with experiment. We also determine a quantitative stress profile and correct breakdown of contributions from lipid components when compared with detailed all-atom simulation benchmarks, which has been difficult to achieve for implicit membrane models. Such a coarse-grained lipid model will be necessary for efficiently simulating complex constructs of the membrane, such as protein assembly and lipid raft formation, within these nonaqueous chemical environments.
Sodt
Alex J
AJ
Department of Bioengineering, University of California, Berkeley, Berkeley, California 94720, USA.
Head-Gordon
Teresa
T
D015060:1,2-Dipalmitoylphosphatidylcholine / Q000031:analogs & derivatives* / Q000737:chemistry*; D003198:Computer Simulation; D002523:Edible Grain; D008051:Lipid Bilayers / Q000737:chemistry*; D008055:Lipids / Q000737:chemistry; D008566:Membranes / Q000737:chemistry; D008958:Models, Molecular; D012997:Solvents; D013816:Thermodynamics
D008051:Lipid Bilayers; D008055:Lipids; D012997:Solvents; D015060:1,2-Dipalmitoylphosphatidylcholine; C081581:colfosceril palmitate