PH Dependence of Charge Multipole Moments in Proteins.

ABSTRACT: Electrostatic interactions play a fundamental role in the structure and function of proteins. Due to ionizable amino acid residues present on the solvent-exposed surfaces of proteins, the protein charge is not constant but varies with the changes in the environment-most notably, the pH of the surrounding solution. We study the effects of pH on the charge of four globular proteins by expanding their surface charge distributions in terms of multipoles. The detailed representation of the charges on the proteins is in this way replaced by the magnitudes and orientations of the multipole moments of varying order. Focusing on the three lowest-order multipoles-the total charge, dipole, and quadrupole moment-we show that the value of pH influences not only their magnitudes, but more notably and im

SUBMITTER: Losdorfer Bozic A 

PROVIDER: S-EPMC5627345 | biostudies-literature | 2017 Oct

REPOSITORIES: biostudies-literature