Effect of a low-dielectric interior on DNA electrostatic response to twisting and bending.
We study the effects of a low-dielectric core of rod-like macromolecules on their electrostatic persistence lengths. We use the exact solution of the linear Poisson-Boltzmann equation for the potential of a charge on the surface of a low-dielectric cylinder. We apply the results to the B-DNA molecule, modeled as a double helical array of discrete charges wound on the surface of a low-dielectric rod. For this charge geometry, we calculate the change in the electrostatic twist persistence as compared to DNA with a water-permeable core. We also discuss possible effects of the low-dielectric molecular core on DNA bending persistence.
Cherstvy
A G
AG
Max-Planck-Institut für Physik komplexer Systeme, Nöthnitzer Strasse 38, 01187 Dresden, Germany.
D004247:DNA / Q000737:chemistry*; D008956:Models, Chemical; D009690:Nucleic Acid Conformation; D055672:Static Electricity; D013499:Surface Properties; D014867:Water / Q000737:chemistry
D014867:Water; D004247:DNA