Surface Electric Properties of Cyanobacterial Thylakoids
All biological membranes, including the thylakoid membrane of photosynthetic organisms, carry fixed electric charges on their surfaces, which are due to exposed ionized groups of molecules that are integrated in the membraie1–6 The reported surface charge density is in the region of 1–3 μC/cm2, in the particular case of thylakoids, the light transducing membrane vesicles of oxygenic photosynthetic organisms. When the electrically charged surface is in contact with a solution of electrolytes, two layers of electric charge are formed, with one layer localized on the surface plane of the membrane and the other, the diffuse layer, localized in the solution.
KeywordsThylakoid Membrane Methyl Viologen Surface Charge Density Apparent Rate Constant P700 Site
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