Gravity effects on membrane processes.

A Schatz; R Reitstetter; A Linke-Hommes; W Briegleb; K Slenzka; H Rahmann

doi:10.1016/0273-1177(94)90383-2

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PubMed · 11537939

Gravity effects on membrane processes.

A Schatz·R Reitstetter·A Linke-Hommes·W Briegleb·K Slenzka·H Rahmann

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Abstract

Application of the Gouy-Chapman-Debye-Hückel (GCDH) theory to a model membrane in contact with electrolytes of various concentrations and composition predict density variations within an interfacial layer. Assuming that on cellular dimensions hydrodynamics can be applied (the objections are briefly discussed) two types of gravity effects can be defined, 1. convection along the surface of vertically oriented membranes and 2. surface potential variations by layer deformations at horizontally oriented membranes. Both effects should affect transport across the layer to the membrane surface and across the membrane. According to the theoretical predictions first experiments with gramicidin channels incorporated into artificial phosphatidylserine bilayer membranes show a significant difference in single channel currents in vertical and horizontal membranes. The complexity of biological membrane functions requires investigation of isolated membrane surface reactions and transport systems to study the gravisensitivity for each process separately.

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Cell Membrane Gramicidin Gravitation Ion Channels Membrane Potentials Membranes, Artificial Models, Biological Phosphatidylserines Phospholipids Rotation Weightlessness Simulation NASA Discipline Cell Biology NASA Discipline Number 40-99 NASA Program Space Biology Research Associates Non-NASA Center Journal Article

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A Schatz, R Reitstetter, A Linke-Hommes, W Briegleb, K Slenzka, H Rahmann. 1994. Gravity effects on membrane processes.. https://doi.org/10.1016/0273-1177(94)90383-2

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