Regulation of Thylakoid Membrane Structure by Surface Electrical Charge
Macroscopic surfaces are a feature of all biological tissue. Although each type of surface will have its own particular structure and composition all will be electrically charged. The extent and polarity of this surface charge will be dictated by the specific components which make-up the surface and by their pK values. In general biological membranes are negatively charged at neutral pH although regions of net positive charge may exist. Particle electrophoresis, and other techniques, have been extensively used to investigate the surface electrical properties of a wide range of biological systems with the view to identifying the chemical nature of the exposed charged groups and their densities. Such studies are of great importance for understanding a wide range of biophysical, biochemical and cellular processes. For example, surface charge governs the concentration of charged solutes at the membrane/liquid interface; affects transmembrane electrical gradients; regulates pH induced phenomena via their pK values; govern the binding of extrinsic proteins; modify ionic conductivity etc. (see ref.1–3).
KeywordsChlorophyll Fluorescence Thylakoid Membrane Surface Charge Density Space Charge Density Mixed Electrolyte
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