The current-voltage relationships of liposomes and mitochondria
- 1 May 1984
- journal article
- research article
- Published by Portland Press Ltd. in Biochemical Journal
- Vol. 219 (3), 719-726
- https://doi.org/10.1042/bj2190719
Abstract
Current-voltage relationships were determined for various membrane systems. We show that phospholipid and mitochondrial membranes exhibit linear relations between H+ flux and pH gradients. These membranes, however, exhibited non-linear relationships when the applied voltage was a membrane potential. The current-voltage relationship approximated to an exponential function. This relationship was found to be linearized when the membranes were treated with an electrogenic proton ionophore. The incorporation of cytochrome c oxidase (EC 1.9.3.1) was found to have no effect on the current-voltage characteristics of the phospholipid membranes. When a membrane potential of more than 140 mV was imposed across vesicular and mitochondrial membranes, they exhibited reversible di-electric breakdown. This phenomenon was correlated with the requirement of a permeant ion for the experimental demonstration of proton translocation by so-called ‘proton pumps’.This publication has 13 references indexed in Scilit:
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