Interfacial water structure controls protein conformation

A. Dér, L. Kelemen, L. Fábián, S. G. Taneva, E. Fodor, T. Páli, A. Cupane, M. G. Cacace, J. J. Ramsden

Research output: Contribution to journalArticle

59 Citations (Scopus)

Abstract

A phenomenological theory of salt-induced Hofmeister phenomena is presented, based on a relation between protein solubility in salt solutions and protein-water interfacial tension. As a generalization of previous treatments, it implies that both kosmotropic salting out and chaotropic salting in are manifested via salt-induced changes of the hydrophobic/hydrophilic properties of protein-water interfaces. The theory is applied to describe the salt-dependent free energy profiles of proteins as a function of their water-exposed surface area. On this basis, three classes of protein conformations have been distinguished, and their existence experimentally demonstrated using the examples of bacteriorhodopsin and myoglobin. The experimental results support the ability of the new formalism to account for the diverse manifestations of salt effects on protein conformation, dynamics, and stability, and to resolve the puzzle of chaotropes stabilizing certain proteins (and other anomalies). It is also shown that the relation between interfacial tension and protein structural stability is straightforwardly linked to protein conformational fluctuations, providing a keystone for the microscopic interpretation of Hofmeister effects. Implications of the results concerning the use of Hofmeister effects in the experimental study of protein function are discussed.

Original languageEnglish
Pages (from-to)5344-5350
Number of pages7
JournalJournal of Physical Chemistry B
Volume111
Issue number19
DOIs
Publication statusPublished - May 17 2007

    Fingerprint

ASJC Scopus subject areas

  • Physical and Theoretical Chemistry
  • Surfaces, Coatings and Films
  • Materials Chemistry

Cite this