Computer simulation of DNA supercoiling.

K V Klenin; A V Vologodskii; V V Anshelevich; A M Dykhne; M D Frank-Kamenetskii

doi:10.1016/0022-2836(91)90745-r

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PubMed · 1994032

Computer simulation of DNA supercoiling.

K V Klenin·A V Vologodskii·V V Anshelevich·A M Dykhne·M D Frank-Kamenetskii

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Abstract

We treat supercoiled DNA within a wormlike model with excluded volume. A modified Monte Carlo approach has been used, which allowed computer statistical-mechanical simulations of moderately and highly supercoiled DNA molecules. Even highly supercoiled molecules do not have a regular shape, though with an increase in writhing the chains look more and more like branched interwound helixes. The averaged writhing (Wr) approximately 0.7 delta Lk. The superhelical free energy F is calculated as a function of the linking number. Lk. The calculations have shown that the generally accepted quadratic dependence of F on Lk is valid for a variety of conditions, though it is by no means universal. Significant deviations from the quadratic dependence are expected at high superhelical density under ionic conditions where the effective diameter of DNA is small. The results are compared with the available experimental data.

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Computer Simulation DNA, Superhelical Monte Carlo Method Nucleic Acid Conformation Thermodynamics Journal Article

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K V Klenin, A V Vologodskii, V V Anshelevich, A M Dykhne, M D Frank-Kamenetskii. 1991-02-05. Computer simulation of DNA supercoiling.. https://doi.org/10.1016/0022-2836(91)90745-r

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