A novel method for measuring the bending rigidity of model lipid membranes by simulating tethers

TL;DR

This paper introduces a simulation-based method to measure lipid membrane bending rigidity by analyzing the force in cylindrical bilayer tethers, aligning well with experimental and theoretical results.

Contribution

It presents a new simulation approach for measuring membrane bending rigidity using tether force analysis, demonstrating consistency with experimental data.

Findings

Simulation method accurately measures bending rigidity.

Results agree with thermal undulation analysis.

No deviations from continuum theory up to bilayer thickness.

Abstract

The tensile force along a cylindrical lipid bilayer tube is proportional to the membrane's bending modulus and inversely proportional to the tube radius. We show that this relation, which is experimentally exploited to measure bending rigidities, can be applied with even greater ease in computer simulations. Using a coarse-grained bilayer model we efficiently obtain bending rigidities that compare very well with complementary measurements based on an analysis of thermal undulation modes. We furthermore illustrate that no deviations from simple quadratic continuum theory occur up to a radius of curvature comparable to the bilayer thickness.