DNA toroid condensation as analytic solutions

Yukitaka Ishimoto; Norio Kikuchi

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arXiv · cond-mat/0701737

DNA toroid condensation as analytic solutions

Yukitaka Ishimoto·Norio Kikuchi

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Abstract

It now becomes apparent that condensed DNA toroid which emerges in a poor solvent condition can be realised in the framework of the non-linear sigma model on a line segment. In fact, the classical solutions of the model, i.e., of the bending potential exhibit toroidal forms, and fit well with the delta-function term of the attractive interaction. The proposed theory is in good agreement with experimental observations that the toroid is the ground state. In this paper, we give a rigorous proof that the solutions are indeed the exact solutions of the equations of motion with the first derivatives of the attractive interaction term. We also show a refined mapping to experimental data, considering the finite size effects of the cross section and of the chain length.

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Yukitaka Ishimoto, Norio Kikuchi. 2007-01-30. DNA toroid condensation as analytic solutions. https://arxiv.org/abs/cond-mat/0701737

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