Efficient tunable generic model for fluid bilayer membranes

TL;DR

This paper introduces a computationally efficient, tunable model for simulating fluid bilayer membranes that self-assemble without explicit solvent and can replicate key physical properties like bending rigidity.

Contribution

The authors develop a simple, robust model for lipid bilayers that accurately captures elastic properties and is adaptable for various physical phenomena without complex solvent interactions.

Findings

Model self-assembles into fluid bilayers across parameter ranges

Physical properties like bending stiffness are tunable within experimental ranges

Suitable for studying membrane phenomena such as fusion and protein interactions

Abstract

We present a model for the efficient simulation of generic bilayer membranes. Individual lipids are represented by one head- and two tail-beads. By means of simple pair potentials these robustly self-assemble to a fluid bilayer state over a wide range of parameters, without the need for an explicit solvent. The model shows the expected elastic behavior on large length scales, and its physical properties (eg fluidity or bending stiffness) can be widely tuned via a single parameter. In particular, bending rigidities in the experimentally relevant range are obtained, at least within $3-30 k_{\text{B}}T$. The model is naturally suited to study many physical topics, including self-assembly, fusion, bilayer melting, lipid mixtures, rafts, and protein-bilayer interactions.