"Electrostatics in Protein Structure and Action"Prof. Huan-Xiang Zhou (Department of Chemistry and Department of Physics, University of Illinois at Chicago)
Proteins are made up of 20 types of amino acids with varying physical properties. Amino acids with ionizable and polar groups, through forming ion pairs, hydrogen bonds, and other less specific electrostatic interactions, impart important properties to proteins. Modulation of the charges on these amino acids, e.g., by pH and by phosphorylation and dephosphorylation, have profound effects such as protein denaturation and switch-like response of signal transduction networks. This talk will present a unifying theme among the various effects of protein charges and polar groups. Simple models will be used to illustrate basic ideas about electrostatic interactions in proteins, and these ideas in turn will be used to elucidate the roles of electrostatic interactions in protein structure, folding, binding, condensation, and related biological functions. In particular, I will examine how charged side chains are spatially distributed in various types of proteins and how electrostatic interactions affect thermodynamic and kinetic properties of proteins. Both important historical developments and recent experimental and theoretical advances in quantifying electrostatic contributions of proteins will be highlighted.