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Electrostatic interactions at charged lipid membranes. Electrostatically induced tilt.

F Jähnig·K Harlos·H Vogel·H Eibl
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Abstract

The changes in bilayer structure induced by surface charges in the case of an ionizable lipid were studied by X-ray diffraction, Raman spectroscopy, and film-balance measurements. With increasing surface charge in the ordered phase, the X-ray results show a decrease in bilayer thickness, whereas the hydrocarbon chain packing stays essentially constant, the Raman data signify that the internal chain ordering does not change, and the monolayer studies show a lateral expansion of the bilayer. These results are interpreted in terms of a tilt of the chains caused by the surface charges on the polar heads. The tilt angle between the direction of the chains and the bilayer normal is obtained by a detailed theoretical evaluation. The tilt allows for a better understanding of the electrostatically induced shift of the phase transition temperature and of the shift induced by the binding of water in the case of lecithin in contrast ethanolamine.

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Hydrogen-Ion ConcentrationMathematicsMembrane LipidsMembranes, ArtificialMolecular ConformationPhosphatidic AcidsSpectrum Analysis, RamanX-Ray DiffractionJournal Article

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F Jähnig, K Harlos, H Vogel, H Eibl. 1979-04-17. Electrostatic interactions at charged lipid membranes. Electrostatically induced tilt.. https://doi.org/10.1021/bi00575a012

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