The paper considers the curvature of double-twisted spirals with different types of twist - the right spiral twisted to the left and the right spiral twisted to the right. Based on the spatial data on DNA structure twisted around the histone backbone, a geometric model of the double-stranded helix was constructed. Using differential geometry formulas, the curvature values along the spiral line were calculated. Two variants of winding the right DNA helix, into the right helix and into the left helix, are considered. It is shown that the alternation of chirality in the hierarchical organization of macromolecules, using DNA as an example, is energetically one and a half times more favorable than in the case of chirality preservation.
chirality, DNA, curvature
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