Stability of the helical configuration of an intrinsically straight semiflexible biopolymer inside a cylindrical cell

We examine the effects of the external force, torque, temperature, confinement, and excluded volume interactions (EVIs) on the stability of the helical configuration of an intrinsically straight semiflexible biopolymer inside a cylindrical cell. We find that to stabilize a helix, the confinement fro...

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Bibliographic Details
Main Authors: Zicong Zhou, Béla Joós, Chen-Xu Wu
Format: Article
Language:English
Published: AIP Publishing LLC 2017-12-01
Series:AIP Advances
Online Access:http://dx.doi.org/10.1063/1.5002145
Description
Summary:We examine the effects of the external force, torque, temperature, confinement, and excluded volume interactions (EVIs) on the stability of the helical configuration of an intrinsically straight semiflexible biopolymer inside a cylindrical cell. We find that to stabilize a helix, the confinement from both ends of the cell is more effective than a uniaxial force. We show that under a uniaxial force and in absence of confinement from bottom of the cell, a stable helix is very short. Our results reveal that to maintain a low pitch helix, a torque acting at both ends of the filament is a necessity, and the confinement can reduce the required torque to less than half making it much easier to form a stable helix. Moreover, we find that thermal fluctuations and EVIs have little impact on the stability of a helix. Our results can help understand the existence of the helix and ring configurations of some semiflexible biopolymers, such as MreB homologs, inside a rod-shaped bacteria.
ISSN:2158-3226