Bending and Twisting Elasticity: a Revised Marko-Siggia Model on DNA Chirality
نویسندگان
چکیده
A revised Marko-Siggia elastic model for DNA double helix [Macromolecules 27, 981 (1994)] is proposed, which includes the WLC bending energy and a new chiral twisting energy term. It is predicted that the mean helical repeat length (HRL) for short DNA rings increases with the decreasing of chain length; while for very long chains, their mean HRL is the same, independent of both the chain length and whether the ends are closed, it is longer than the value for rectilinear DNAs. Our results are in good agreement with
منابع مشابه
Chiral elasticity of DNA
DNA has been described as a semiflexible polymer. But DNA is chiral, so its bending Hamiltonian contains nonlinear terms coupling the curvature κ to the torsion τ , leading to an average 〈τ〉 independent of κ, and variance 〈∆τ〉 scaling as 1/κ. We perform atomistic MD simulations of 31 base-pair DNA sequences with explicit solvent, in which “restraints” are imposed to “encourage” the DNA to bend....
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