Discrete elastic model for stretching-induced flagellar polymorphs
Abstract
Force-induced reversible transformations between coiled and normal polymorphs of bacterial flagella have been observed in recent optical-tweezer experiment. We introduce a discrete elastic rod model with two competing helical states governed by a fluctuating spin-like variable that represents the underlying conformational states of flagellin monomers. Using hybrid Brownian dynamics Monte-Carlo simulations, we show that a helix undergoes shape transitions dominated by domain wall nucleation and motion in response to externally applied uniaxial tension. A scaling argument for the critical force is presented in good agreement with experimental and simulation results. Stretching rate-dependent elasticity including a buckling instability are found, also consistent with the experiment.
Cite
@article{arxiv.0804.0893,
title = {Discrete elastic model for stretching-induced flagellar polymorphs},
author = {Hirofumi Wada and Roland R. Netz},
journal= {arXiv preprint arXiv:0804.0893},
year = {2008}
}