To the top

Page Manager: Webmaster
Last update: 9/11/2012 3:13 PM

Tell a friend about this page
Print version

Concentration-Induced Ass… - University of Gothenburg, Sweden Till startsida
Sitemap
To content Read more about how we use cookies on gu.se

Concentration-Induced Association in a Protein System Caused by a Highly Directional Patch Attraction

Journal article
Authors Weimin Li
Björn A. Persson
Mikael Lund
Johan Bergenholtz
Malin Zackrisson Oskolkova
Published in Journal of Physical Chemistry B
Volume 120
Pages 8953-8959
ISSN 1520-6106
Publication year 2016
Published at Department of Chemistry and Molecular Biology
Pages 8953-8959
Language en
Links pubs.acs.org/doi/abs/10.1021/acs.jp...
Keywords protein interactions, SAXS, light scattering, integral equation theory, structure factor
Subject categories Biophysical chemistry, Surface and colloid chemistry, Statistical mechanics

Abstract

Self-association of the protein lactoferrin is studied in solution using small-angle X-ray scattering techniques. Effective static structure factors have been shown to exhibit either a monotonic or a nonmonotonic dependence on protein concentration in the small wavevector limit, depending on salt concentration. The behavior correlates with a nonmonotonic dependence of the second virial coefficient on salt concentration, such that a maximum appears in the structure factor at a low protein concentration when the second virial coefficient is negative and close to a minimum. The results are interpreted in terms of an integral equation theory with explicit dimers, formulated by Wertheim, which provides a consistent framework able to explain the behavior in terms of a monomer–dimer equilibrium that appears because of a highly directional patch attraction. Short attraction ranges preclude trimer formation, which explains why the protein system behaves as if it were subject to a concentration-dependent isotropic protein–protein attraction. Superimposing an isotropic interaction, comprising screened Coulomb repulsion and van der Waals attraction, on the patch attraction allows for a semiquantitative modeling of the complete transition pathway from monomers in the dilute limit to monomer–dimer systems at somewhat higher protein concentrations.

Page Manager: Webmaster|Last update: 9/11/2012
Share:

The University of Gothenburg uses cookies to provide you with the best possible user experience. By continuing on this website, you approve of our use of cookies.  What are cookies?