Change of Surface Potential and Intramembrane Electrical Field Induced by the Movements of Hydrophobic Ions Inside Chromatophore Membranes of Rhodopseudomonas sphaeroides Studied by Responses of Merocyanine Dye and Intrinsic Carotenoids

Abstract

Change of the ionic conditions or pH of the outer medium changes surface potential of energy transducing membranes as expected from the Gouy-Chapman theory and affect electrical field within the membrane under some conditions (1,2). This induces a change of the redox states of electron carriers inside membrane depending on their intramembrane localization (3,4). Thus, change of surface potential is expected to affect the movement of electrons and ions within the membrane as well as the reaction rates at the membrane surface (3). Vice versa, energization of the membranes are expected to induce changes of surface potential value as experimentally suggested in some membrane systems (3,5).