Coarse-Grain Model for Lipid Bilayer Self-Assembly and Dynamics: Multiparticle Collision Description of the Solvent

TL;DR

This paper introduces a mesoscopic coarse-grain model combining molecular dynamics for lipids and multiparticle collision dynamics for solvent, enabling efficient simulation of membrane self-assembly, phase behavior, and mechanical properties.

Contribution

It presents a novel hybrid simulation approach that captures lipid bilayer self-assembly, phase transitions, and membrane mechanics at a mesoscopic scale.

Findings

Successful simulation of membrane self-assembly from lipid mixtures

Reproduction of gel and liquid phases of bilayers at different temperatures

Analysis of lipid diffusion and membrane flow dynamics

Abstract

A mesoscopic coarse-grain model for computationally-efficient simulations of biomembranes is presented. It combines molecular dynamics simulations for the lipids, modeled as elastic chains of beads, with multiparticle collision dynamics for the solvent. Self-assembly of a membrane from a uniform mixture of lipids is observed. Simulations at different temperatures demonstrate that it reproduces the gel and liquid phases of lipid bilayers. Investigations of lipid diffusion in different phases reveals a crossover from subdiffusion to normal diffusion at long times. Macroscopic membrane properties, such as stretching and bending elastic moduli, are determined directly from the mesoscopic simulations. Velocity correlation functions for membrane flows are determined and analyzed.