Macroscopic electrostatic models for protonation states in proteins
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Sedimentation Equilibrium of a Small Oligomer-forming Membrane Protein: Effect of Histidine Protonation on Pentameric Stability
Published on: April 2, 2015
1Department of Molecular Biotechnology, Hartwell Center for Bioinformatics and Biotechnology, Saint Jude Children's Research Hospital, Memphis, TN 38105-2794, USA. Doon.Bashford@stjude.org
Abstract:
The use of macroscopic electrostatic models to calculate the relative energetics of protonation states and the pH-titration properties of ionizable groups in proteins is described. These methods treat the protein as an irregularly-shaped low-dielectric object containing embedded atomic charges immersed in a high-dielectric (solvent) medium. The energetics of altering protonation states then involves the electrostatic work of altering the embedded atomic charges. The governing electrostatic equation is either the Poisson or linearized Poisson-Boltzmann equation, which generally requires numerical solution. A tutorial approach is taken, the main aim of which is a thorough understanding of the method.
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