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arXiv · 0809.1343

Writhe formulas and antipodal points in plectonemic DNA configurations

S. Neukirch·E. L. Starostin
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Abstract

The linking and writhing numbers are key quantities when characterizing the structure of a piece of supercoiled DNA. Defined as double integrals over the shape of the double-helix, these numbers are not always straightforward to compute, though a simplified formula exists. We examine the range of applicability of this widely-used simplified formula, and show that it cannot be employed for plectonemic DNA. We show that inapplicability is due to a hypothesis of Fuller theorem that is not met. The hypothesis seems to have been overlooked in many works.

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S. Neukirch, E. L. Starostin. 2008-09-08. Writhe formulas and antipodal points in plectonemic DNA configurations. https://doi.org/10.1103/physreve.78.041912

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