1] Electrostatic effects in protein folding, stability, and function

Abstract

Publisher Summary This chapter discusses the electrostatic effects in protein folding, stability, and function. The structure, stability, and biological function of a folded protein depend on a complex interplay among the packing and bonding potentials of its constituent amino acid residues and their interactions with the solvent. The developments in the area of electrostatic effects in protein folding, stability, and function have been driven primarily by advances in high-speed computing and methods for site-directed mutagenesis. As a result, the emphasis has been on developing sophisticated models and resolving the energetics of specific interactions. The most widely used methods at present for modeling whole proteins are based on the Poisson–Boltzmann equation, in which solvent and mobile ions are treated statistically (continuum models) rather than microscopically. The electrostatic effects that contribute to protein folding, stability, and function involve monopole, dipole, and even quadrupole interactions within the protein and interactions with solvent. Many examples of these interactions have been pointed out in the analyses of crystal structures, including ion-dipole interactions in helices, interactions among ions and polarized peptide units at active sites, and weakly polar interactions among aromatic side chains being foci of recent interest.