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Conformations of Linear DNA

Boris Fain·Joseph Rudnick·Stellan Ostlund
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Abstract

We examine the conformations of a model for under- and overwound DNA. The molecule is represented as a cylindrically symmetric elastic string subjected to a stretching force and to constraints corresponding to a specification of the link number. We derive a fundamental relation between the Euler angles that describe the curve and the topological linking number. Analytical expressions for the spatial configurations of the molecule in the infinite- length limit were obtained. A unique configuraion minimizes the energy for a given set of physical conditions. An elastic model incorporating thermal fluctuations provides excellent agreement with experimental results on the plectonemic transition.

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Boris Fain, Joseph Rudnick, Stellan Ostlund. 1996-10-15. Conformations of Linear DNA. https://doi.org/10.1103/physreve.55.7364

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