Bending and Base-Stacking Interactions in Double-Stranded Semiflexible Polymer
نویسندگان
چکیده
Simple expressions for the bending and the base-stacking energy of double-stranded semiflexible biopolymers (such as DNA and actin) are derived. The distribution of the folding angle between the two strands is obtained by solving a Schrödinger equation variationally. Theoretical results based on this model on the extension versus force and extension versus degree of supercoiling relations of DNA chain are in good agreement with the experimental observations of Cluzel et al. [Science 271, 792 (1996)], Smith et al. [ibid. 271, 795 (1996)], and Strick et al. [ibid. 271, 1835 (1996)].
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