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Updated: Jan 11, 2026

Magnetic Tweezers for the Measurement of Twist and Torque
Published on: May 19, 2014
Exact statistics of helical wormlike chains with twist-bend coupling
Ashesh Ghosh1,2,3, Kranthi K Mandadapu2,3, David T Limmer1,3,4,5
1University of California, Berkeley, Department of Chemistry, California 94720, USA.
Abstract:
We present a solution for the Green's function for the general case of a helical wormlike chain with twist-bend coupling and demonstrate the applicability of our solution for evaluating general structural and mechanical chain properties. We find that twist-bend coupling renormalizes the persistence length and the force-extension curves relative to wormlike chains. Analysis of intrinsically twisted polymers shows that incorporation of twist-bend coupling results in the oscillatory behavior in principal tangent correlations that are observed in some studies of synthetic polymers. The exact nature of our solution provides a framework to evaluate the role of twist-bend coupling on polymer properties, such as DNA bound to histones and motivates the reinterpretation of existing biopolymer experimental data.
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