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Direct Determination of DNA Twist-Stretch Coupling

Randall D. Kamien·Tom C. Lubensky·Philip Nelson·Corey S. O'Hern
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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. [Science 271 (1996) 1835] 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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Randall D. Kamien, Tom C. Lubensky, Philip Nelson, Corey S. O'Hern. 1996-11-27. Direct Determination of DNA Twist-Stretch Coupling. https://doi.org/10.1209/epl%2Fi1997-00231-y

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