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arXiv · 1510.02986

Application of a Free Energy Landscape Approach to Study Tension Dependent Bilayer Tubulation Mediated by Curvature Inducing Proteins

Richard W. Tourdot·N. Ramakrishnan·Tobias Baumgart·Ravi Radhakrishnan
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Abstract

We investigate the phenomenon of protein induced tubulation of lipid bilayer membranes within a continuum framework using Monte Carlo simulations coupled with the Widom insertion technique to compute excess chemical potentials. Tubular morphologies are spontaneously formed when the density and the curvature-field strength of the membrane bound proteins exceed their respective thresholds and this transition is marked by a sharp drop in the excess chemical potential. We find that the planar to tubular transition can be described by a micellar model and that the corresponding free energy barrier increases with increase in the curvature-field strength, (i.e. of protein-membrane interactions), and also with increase in membrane tension.

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Richard W. Tourdot, N. Ramakrishnan, Tobias Baumgart, Ravi Radhakrishnan. 2015-10-10. Application of a Free Energy Landscape Approach to Study Tension Dependent Bilayer Tubulation Mediated by Curvature Inducing Proteins. https://arxiv.org/abs/1510.02986

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