The adsorption of divalent cations to phosphatidylglycerol bilayer membranes

doi:10.1016/0005-2736(81)90199-1

Biochimica et Biophysica Acta (BBA) - Biomembranes

Volume 645, Issue 2, 20 July 1981, Pages 279-292

https://doi.org/10.1016/0005-2736(81)90199-1 Get rights and content

Abstract

The ability of the Stern equation to describe the adsorption of divalent cations to phosphatidylglycerol membranes was tested by combining ³¹P-NMR and electrophoretic mobility measurements. In 0.1 M sodium chloride both the ³¹P-NMR and the zeta potential data are well described by the Stern equation. ³¹P-NMR and ¹³C-NMR results indicate that cobalt forms inner-sphere complexes only with the phosphate group of phosphatidylglycerol molecules and that a substantial fraction of the adsorbed cobalt ions form outer-sphere complexes. Evidence is presented that suggests the alkaline earth cations also bind to phospholipids mainly by forming outer sphere complexes. Electrophoretic mobility measurements were performed with several different divalent cations. In all cases the zeta potentials in 0.1 M sodium chloride were well described by the Stern equation. The intrinsic 1 : 1 association constants (M⁻¹) for the phosphatidylglycerol complexes decreased in the sequence: Mn²⁺, 11.5; Ca²⁺, 8.5; Ni²⁺, 7.5; Co²⁺, 6.5; Mg²⁺, 6.0; Ba²⁺, 5.5 and Sr²⁺, 5.0.

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The adsorption of divalent cations to phosphatidylglycerol bilayer membranes

Abstract

Coord. Chem. Rev.

Biochim. Biophys. Acta

J. Magn. Reson.

J. Magn. Reson.

Biochim. Biophys. Acta

FEBS Lett.

Curr. Top. Membrane Transp.

Biochim. Biophys. Acta

Biochim. Biophys. Acta

J. Biol. Chem.

J. Colloid Interface Sci.

Bioelectrochem. Bioenerg.

Biochim. Biophys. Acta

J. Colloid Interfacial Sci.

J. Theor. Biol.

Biophys. J.

J. Theor. Biol.

Biochemistry

J. Gen. Physiol.

Mechanisms of Inorganic Reactions

Nature

J. Chem. Phys.

J. Chem. Phys.

Biochemistry