Coarse-grained DMPC bilayer /water simulation system
In this study, we have used a coarse-grained model to investigate the lipid bilayer-water system. Here the lipid bilayer we chose is dimyristoylphosphatidylcholine (DMPC) bilayer. The coarse-grained force field is based on a four-to-one mapping, i.e., on average, four heavy atoms are represented by a single interaction site. The mapping of a coarse-grained water site (P4) is shown in the image. For the lipids, the same mapping strategy is applied and the phospholipid DMPC is modeled using 10 coarse-grained sites. By applying the coarse-grain model, we use an effective force field to describe the site-site interaction, decreased the number of interaction sites and are able to speed up the simulation 10 times faster, which enable us to study more complex biological systems. We checked the thickness of the coarse-grained DMPC lipid bilayer which is measured from the peaks of the phosphate distribution. From the image we can get clear idea of the interface of lipid-water and the thickness of lipid membrane.