Evaluation of ion binding to DNA duplexes using a size-modified Poisson-Boltzmann theory.

ABSTRACT: Poisson-Boltzmann (PB) theory is among the most widely applied electrostatic theories in biological and chemical science. Despite its reasonable success in explaining a wide variety of phenomena, it fails to incorporate two basic physical effects, ion size and ion-ion correlations, into its theoretical treatment. Recent experimental work has shown significant deviations from PB theory in competitive monovalent and divalent ion binding to a DNA duplex. The experimental data for monovalent binding are consistent with a hypothesis that attributes these deviations to counterion size. To model the observed differences, we have generalized an existing size-modified Poisson-Boltzmann (SMPB) theory and developed a new numerical implementation that solves the generalized theory around complex, atom

SUBMITTER: Chu VB 

PROVIDER: S-EPMC2025650 | biostudies-literature | 2007 Nov

REPOSITORIES: biostudies-literature