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Updated: Jun 1, 2026
09:38
Biomembrane Fabrication by the Solvent-assisted Lipid Bilayer (SALB) Method
Published on: December 1, 2015
Water order profiles on phospholipid/cholesterol membrane bilayer surfaces
David Robinson1, Nicholas A Besley, Paul O'Shea
1School of Chemistry, University of Nottingham, Nottingham, United Kingdom.
Journal of Computational Chemistry
|June 3, 2011
Summary
Surface water near biological membranes is more ordered than bulk water, impacting membrane properties. This ordering affects hydrogen bonding and dielectric permittivity, revealing differences between lipid and cholesterol membrane structures.
Area of Science:
- Biophysics
- Physical Chemistry
Background:
- Water plays a crucial role in stabilizing biological macromolecules.
- The dynamic structure of water at molecular surfaces remains incompletely understood.
Purpose of the Study:
- To investigate the structural and dynamic properties of water at membrane surfaces.
- To understand how water ordering influences membrane dielectric properties and hydrogen bonding.
Main Methods:
- Molecular simulations were employed to model water-membrane interactions.
- Fluorescence measurements were utilized to probe water structure and dynamics.
Main Results:
- Water at the membrane surface exhibits greater order than bulk water due to reduced hydrogen bonding and aligned dipole moments.
- A gradient in effective dielectric permittivity was observed, correlating with decreased hydrogen bonding.
- Water molecules near lipid headgroups showed significantly longer hydrogen bond lifetimes (6.3 ps) compared to bulk water (<2 ps).
- Distinct differences in water ordering were found between pure phosphatidylcholine (PC) membranes and PC/cholesterol mixtures.
Conclusions:
- Membrane surface water exhibits unique structural and dynamic characteristics.
- The observed water ordering and altered dielectric properties influence membrane biophysics.
- Differences in membrane composition, such as cholesterol content, lead to variations in surface water structure and properties.
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