Chapter

Chapter 22.3 Electrostatic interactions in proteins

Crystallography of biological macromolecules

First Online Edition (2006)

Part 22. Molecular geometry and features

  1. K. A. Sharp

Published Online: 1 JAN 2006

DOI: 10.1107/97809553602060000712

International Tables for Crystallography

International Tables for Crystallography

How to Cite

Sharp, K. A. 2006. Electrostatic interactions in proteins. International Tables for Crystallography. F:22:22.3:553–557.

Author Information

  1. E. R. Johnson Research Foundation, Department of Biochemistry and Biophysics, University of Pennsylvania, Philadelphia, PA 19104-6059, USA

Publication History

  1. Published Online: 1 JAN 2006

Abstract

Electrostatic interactions play a key role in determining the structure, stability, binding affinity and chemical properties, and hence the biological reactivity, of proteins and nucleic acids. The goal of electrostatic calculations is to take the structural information provided by crystallography or NMR and obtain a realistic description of the electrostatic potential distribution ϕ(r), energies and forces. Three problems must be solved to obtain the electrostatic potential distribution: modelling the macromolecular charge distribution; modelling the response of the macromolecule, water and solvent ions; and rapidly and accurately solving the electrostatic equations that determine the potential. The response arises from electronic polarization, reorientation of permanent dipolar groups and redistribution of mobile ions in the solvent. The most common theoretical approaches to modelling this response are briefly described, along with the methods used to obtain potential distributions, energies and forces. A summary of the theory behind application to three broad areas is presented: electrostatic potential distributions, charge (proton and electron) transfer equilibria, and electrostatic contributions to binding energies.

Keywords:

  • binding energies;
  • charge-transfer equilibria;
  • electrostatic fields;
  • electrostatic interactions in proteins;
  • electrostatic potential;
  • electrostatics