Protein diffusion in crowded electrolyte solutions

Research output: Contribution to journalArticle

Abstract

We report on a combined cold neutron backscattering and spin-echo study of the short-range and long-range nanosecond diffusion of the model globular protein bovine serum albumin (BSA) in aqueous solution as a function of protein concentration and NaCl salt concentration. Complementary small angle X-ray scattering data are used to obtain information on the correlations of the proteins in solution. Particular emphasis is put on the effect of crowding, i.e. conditions under which the proteins cannot be considered as objects independent of each other. We thus address the question at which concentration this crowding starts to influence the static and in particular also the dynamical behaviour. We also briefly discuss qualitatively which charge effects, i.e. effects due to the interplay of charged molecules in an electrolyte solution, may be anticipated. Both the issue of crowding as well as that of charge effects are particularly relevant for proteins and their function under physiological conditions, where the protein volume fraction can be up to approximately 40% and salt ions are ubiquitous. The interpretation of the data is put in the context of existing studies on related systems and of existing theoretical models.

Details

Authors
  • Felix Roosen-Runge
  • Marcus Hennig
  • Tilo Seydel
  • Fajun Zhang
  • Maximilian W.A. Skoda
  • Stefan Zorn
  • Robert M.J. Jacobs
  • Marco Maccarini
  • Peter Fouquet
  • Frank Schreiber
External organisations
  • University of Tübingen
  • Institut Laue Langevin
  • Rutherford Appleton Laboratory
  • University of Oxford
Research areas and keywords

Keywords

  • Cold neutron backscattering spectroscopy, Globular proteins in aqueous solution, Neutron spin echo spectroscopy, Quasi-elastic neutron scattering, Salt ions
Original languageEnglish
Pages (from-to)68-75
Number of pages8
JournalBiochimica et Biophysica Acta - Proteins and Proteomics
Volume1804
Issue number1
Publication statusPublished - 2010 Jan 1
Publication categoryResearch
Peer-reviewedYes
Externally publishedYes