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arXiv · 0804.0893

Discrete elastic model for stretching-induced flagellar polymorphs

Hirofumi Wada·Roland R. Netz
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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.

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Hirofumi Wada, Roland R. Netz. 2008-04-06. Discrete elastic model for stretching-induced flagellar polymorphs. https://doi.org/10.1209/0295-5075/82/28001

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