Influence of polar co-solutes and salt on the hydration of lipid membranes

Research output: Contribution to journalArticle

Abstract

The influence of the co-solutes TMAO, urea, and NaCl on the hydration repulsion between lipid membranes is investigated in a combined experimental/simulation approach. Pressure-hydration curves obtained via sorption experiments reveal that the repulsion significantly increases when the membranes are loaded with co-solutes, most strongly for TMAO. As a result, the co-solutes retain additional water molecules and therefore provide membranes with a fluid and more physiological environment. The experimental data are quantitatively reproduced in complementary solvent-explicit atomistic molecular dynamics simulations, which yield the chemical potential of water. Simulation analysis reveals that the additional repulsion arises from the osmotic pressure generated by the co-solutes, an effect which is maximal for TMAO, due to its unfavorable interactions with the lipid headgroup layer and its extraordinarily high osmotic coefficient.

Details

Authors
Organisations
External organisations
  • Free University of Berlin
  • University Grenoble Alpes
  • Max Planck Institute of Colloids and Interfaces
Research areas and keywords

Subject classification (UKÄ) – MANDATORY

  • Biophysics
Original languageEnglish
Pages (from-to)16989-17000
Number of pages12
JournalPhysical Chemistry Chemical Physics
Volume21
Issue number31
Publication statusPublished - 2019
Publication categoryResearch
Peer-reviewedYes