Salt Effects on Protein-DNA Interactions: The λcI Repressor and EcoRI Endonuclease

摘要: In this paper, finite-difference solutions to the nonlinear Poisson-Boltzmann (NLPB) equation are used calculate salt dependent contribution electrostatic DNA binding free energy for both λcI repressor and EcoRI endonuclease. For protein-DNA systems studied, NLPB method describes nonspecific univalent effects on which in excellent agreement with experimental results. these systems, of ion atmosphere substantially destabilizes complexes. The magnitude effect involves a macromolecular structure redistribution cations anions around protein is dominated by long range interactions. We find that associated global upon more important than changes local interactions (ion-pairs) determining effects. model reveals how can play significant role relative stability complexes different structures.