Proton permeability of liposomes from natural phospholipid mixtures

doi:10.1016/0005-2736(82)90005-0

Biochimica et Biophysica Acta (BBA) - Biomembranes

Volume 684, Issue 2, 22 January 1982, Pages 195-199

https://doi.org/10.1016/0005-2736(82)90005-0 Get rights and content

Abstract

A method to determine the proton permeability coefficient of phospholipid membrane with the fluorescent probe pyranine is described. Very high proton permeability coefficients of liposomes from natural extracts are measured with great accuracy. The proton permeability appears to be linearly related to the fluidity of the bilayers. This relation as well as the comparison of the activation energies of proton permeability and fluidity support the hypothesis (Nichols J.W. and Deamer D.W. (1980) Proc. Natl. Acad. Sci. USA 77, 2038–2042) of a transfer process along a network of hydrogen bonded water molecules. It is suggested that the common lipid characteristics of biological membranes (net surface charge and unsaturation) favor a high proton permeability.

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Citation Excerpt :
Under these conditions, the proton flux JH across the membrane (Eq. (10)) and the characteristic time τH of proton relaxation (Eq. (6)) both depend on pH. Nonetheless the proton permeability of membrane PH, which relates these two characteristics (cf. Eqs. (3) and (6)), is a pH-independent parameter. The obtained value of PH is within the proton permeability range of 10−4–10−8 cm s−1, as measured with different lipid bilayers [7–21]. We analyzed our MD simulation data to trace the presence of unsupported water clusters in the hydrophobic part of the membrane (the systems B, C were inspected, see Table 1).
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Citation Excerpt :
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Biochimica et Biophysica Acta (BBA) - Biomembranes

Abstract

References (19)

J. Lipid Res.

Phytochemistry

Biochim. Biophys. Acta

Biochim. Biophys. Acta

Biochim. Biophys. Acta

Chem. Phys. Lipids

Biochim. Biophys. Acta

Biochim. Biophys. Acta

Biochim. Biophys. Acta

Cited by (75)

Quantifying proton-induced membrane polarization in single biomimetic giant vesicles

Ultrasensitive liposome-based assay for the quantification of fundamental ion channel properties

Proton leakage across lipid bilayers: Oxygen atoms of phospholipid ester linkers align water molecules into transmembrane water wires

Effects of Lipid Tethering in Extremophile-Inspired Membranes on H<sup>+</sup>/OH<sup>-</sup> Flux at Room Temperature

Distribution and dynamics of OXPHOS complexes in the bacterial cytoplasmic membrane

Faster-than-anticipated Na<sup>+</sup>/Cl<sup>-</sup> diffusion across lipid bilayers in vesicles