Coarse-Grained Models of Biological Membranes within the Single Chain Mean Field Theory

TL;DR

This paper employs Single Chain Mean Field theory to simulate phospholipid membranes at various coarse-grained levels, demonstrating that even minimal models can accurately reproduce key membrane properties efficiently.

Contribution

It introduces a multi-level coarse-grained modeling approach within the SC-MF framework, showing minimal models can effectively capture membrane equilibrium properties.

Findings

All models reproduce essential membrane properties.

The minimal 3-beads model is computationally fastest.

The method compares favorably with Monte Carlo simulations.

Abstract

The Single Chain Mean Field theory is used to simulate the equilibrium structure of phospholipid membranes at the molecular level. Three levels of coarse-graining of DMPC phospholipid surfactants are present: the detailed 44-beads double tails model, the 10-beads double tails model and the minimal 3-beads model. We show that all three models are able to reproduce the essential equilibrium properties of the phospholipid bilayer, while the simplest 3-beads model is the fastest model which can describe adequately the thickness of the layer, the area per lipid and the rigidity of the membrane. The accuracy of the method in description of equilibrium structures of membranes compete with Monte Carlo simulations while the speed of computation and the mean field nature of the approach allows for straightforward applications to systems with great complexity.