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Twist-Stretch Elasticity of DNA

C. S. O'Hern·Randall D. Kamien·T. C. Lubensky·Philip Nelson
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Abstract

The symmetries of the DNA double helix require a new term in its linear response to stress: the coupling between twist and stretch. Recent experiments with torsionally-constrained single molecules give the first direct measurement of this important material parameter. We extract its value from a recent experiment of Strick, et al. and find rough agreement with an independent experimental estimate recently given by Marko. We also present a very simple microscopic theory predicting a value comparable to the one observed.

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C. S. O'Hern, Randall D. Kamien, T. C. Lubensky, Philip Nelson. 1996-12-09. Twist-Stretch Elasticity of DNA. https://arxiv.org/abs/cond-mat/9612085

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