Biopolymers and cell. 1988. Volume 4. № 2. 85 - 90

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

TOPOLOGICAL CHARACTERISTICS OF CIRCULAR DMA: EXCLUDED VOLUME EFFECTS

Summary

    The Monte Carlo method is used to calculate the probability p of knots formation, the variance of the writhing number 2> and the expansion factor a for a closed polymer chain as a function of its effective diameter d. The results are presented in a form of simple interpolation equations and applied for DNA. The dependence of DNA super-helix energy on its effective diameter is evaluated. Theory predicts significant dependence of the superhelix energy on ionic strength.