New measurements of DNA twist elasticity.
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 new material parameter. We extract its value from a recent experiment. Finally, we sketch the effect of constrained twist on entropic elasticity of DNA arising from the connection between Link, Twist, and Writhe.
Nelson
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Department of Physics and Astronomy, University of Pennsylvania, Philadelphia 19104, USA. nelson@hollebeek.hep.upenn.edu
D004247:DNA / Q000737:chemistry*; D004548:Elasticity; D019277:Entropy; D008956:Models, Chemical; D009690:Nucleic Acid Conformation; D013314:Stress, Mechanical
D004247:DNA