Persistence length bending

The (bending) persistence length of DNA, which is proportional to its bending rigidity, has been extensively studied for well over two decades, usually via its effect on the overall dimensions of the DNA coil. This work... 

The simulation procedure was generalized by Allison et al.<2f>9> to treat both symmetric and asymmetric anisotropic bending, as well as permanent bends. Symmetric anisotropic bending is found to have little effect for times longer than a few nanoseconds, provided the long-range persistence length(85)... 

As the persistence length P approaches infinity, the bending relaxation times T all approach zero, and the amplitude of the uniform mode approaches 1.0, in which case F (l) is precisely the result for a rigid (against flexure) rod. 

A prerequisite to these calculations is the knowledge of bending and torsional rigidity coefficients (A and C, respectively) of the naked DNA. A was calculated from a persistence length a = A/kT = 50 nm [58], and C through the following equation, valid only for a naked DNA minicircle near relaxation [59]... 

For coarse-grained models of linear biopolymers—such as DNA or chromatin— two types of interactions play a role. The connectivity of the chain implies stretching, bending, and torsional potentials, which exist only between directly adjacent subunits and are harmonic for small deviations from equilibrium. As mentioned above, these potentials can be directly derived from the experimentally known persistence length or by directly measuring bulk elastic properties of the chain. 

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