title: Swing motion as a diffusion mechanism of lipid bilayers in a gel phase.
abstract: Lipid bilayers are a model system for studying the properties of cell membranes. For lipid bilayers of a single lipid component, there is a phase transition from a fluid phase to a gel phase as the temperature is decreased. The dynamic behavior of lipids in the gel phase is interesting: some models show dynamic heterogeneity with a large disparity in timescales between fast and slow molecules, and a spatial segregation of the slow molecules. In this paper we study the dynamics of coarse-grained models of lipid bilayers using the dry Martini, Lennard-Jones Martini, polarizable Martini, and BMW models. All four models show similar dynamical behaviors in the gel phase although the transition temperature is model-dependent. We find that the primary mode of transport in the gel phase is a hopping of the lipid molecules. Hopping is seen in both the translational and rotational dynamics, which are correlated, i.e., the lipid molecules display a swing-like motion in the gel phase.
authors: Department of Chemistry and Research Institute for Basic Science, Sogang University, Seoul 121-742, Republic of Korea.
authors: Younghoon
authors: Y
authors: Oh
authors: Department of Chemistry and Research Institute for Basic Science, Sogang University, Seoul 121-742, Republic of Korea.
authors: Jeongmin
authors: J
authors: Kim
authors: Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA.
authors: Arun
authors: A
authors: Yethiraj
authors: Department of Chemistry and Research Institute for Basic Science, Sogang University, Seoul 121-742, Republic of Korea.
authors: Bong June
authors: BJ
authors: Sung
mesh_terms: D015060:1,2-Dipalmitoylphosphatidylcholine / Q000737:chemistry; D002462:Cell Membrane / Q000737:chemistry; D003198:Computer Simulation; D004058:Diffusion; D005782:Gels; D008051:Lipid Bilayers / Q000737:chemistry*; D008954:Models, Biological; D009038:Motion; D044367:Phase Transition; D044366:Transition Temperature; D014867:Water / Q000737:chemistry
chemical_list: D005782:Gels; D008051:Lipid Bilayers; D014867:Water; D015060:1,2-Dipalmitoylphosphatidylcholine