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Updated: Jun 21, 2026

Neutron Spin Echo Spectroscopy as a Unique Probe for Lipid Membrane Dynamics and Membrane-Protein Interactions
Published on: May 27, 2021
Effect of sterol structure on the bending rigidity of lipid membranes: A (2)H NMR transverse relaxation study
Greger Orädd1, Vahid Shahedi, Göran Lindblom
1Department of Chemistry, Umeå University, SE-901 87 Umeå, Sweden. greger.oradd@chem.umu.se
Abstract:
The effect of incorporation of 3-43 mol% sterol on the lipid order and bilayer rigidity has been investigated for model membranes of dimyristoylphosphatidylcholine or dipalmitoylphosphatidylcholine. (2)H NMR spectra and spin-lattice relaxation rates were measured for macroscopically aligned bilayers. The characteristics of spectra obtained at temperatures between 0-60 degrees Celsius are interpreted in terms of a two-phase coexistence of the liquid disordered and the liquid ordered phases and the data is found to be in agreement with the phase diagram published by Vist and Davis (Biochemistry 29 (1990), pp. 451-464). The bending modulus of the bilayers was calculated from plots of relaxation rate vs. the square of the order parameter at 44 degrees Celsius. Clear differences were obtained in the efficiency of the sterols to increase the stiffness of the bilayers. These differences are correlated to the ability of the sterols to induce the liquid ordered phase in binary as well as in ternary systems; the only exception being ergosterol, which was found to be unable to induce l(o) phases and also had a relatively weak effect on the bilayer stiffness in contrast to earlier reports.
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