Allowance for spatial dispersion of dielectric permittivity in polyelectrolyte model of DNA.
In order to allow for real dielectric properties of a solvent in calculating of electrostatic characteristics of strongly charged polyions such as DNA in salt solution we consider a simple model of linear dielectric response of a medium. The interactions between charged particles are treated in the framework of self-consistent-field approximation. The basic characteristic of the problem, electrostatic potential, can be found from the solution of non-linear integro-differential equation. Specifically we consider so-called quasimacroscopic model where dielectric response of a medium depends only on the distance from the polyion. Application of the approach for calculating of the B-to-Z free energy qualitatively retains the main conclusion obtained previously within the model with fixed dielectric constant: non-monotonous behavior of the free energy differences as a function of ionic strength. At the same time, essential sensitivity of the results to specific values of dielectric parameters is observed.
Lukashin
A V
AV
Institute of Molecular Genetics, USSR Academy of Sciences, Moscow.
Beglov
D B
DB
Frank-Kamenetskii
M D
MD
D004247:DNA / Q000737:chemistry*; D004573:Electrolytes / Q000737:chemistry*; D008956:Models, Chemical; D009690:Nucleic Acid Conformation; D012997:Solvents; D013816:Thermodynamics
D004573:Electrolytes; D012997:Solvents; D004247:DNA