Characterization of the Heat Induced Effects on the Physical Properties and Organization State of PSII Subchloroplast Membranes
The inhibitory effect of heating on the PSII-associated photochemical activity and heat-induced changes in the structural organization and electrical properties of thylakoid membranes are well established1,2,3. Although the heat inactivation of oxygen evolution in isolated PSII particles and the concominant alterations in the electron donor site of PSII (partial protein and Mn2+ release from the particles) have been also reported4,5 , little is known about heat-induced effects on the physical properties and organization state of PSII membranes. In the present study we have reported a decrease of the net negative surface charge density in heat treated PSII membranes. In addition, 77K fluorescence measurements have indicated that structural reorganization of chlorophyll-protein complexes (LHCa/b and PSII core) also occur under the same conditions.
KeywordsThylakoid Membrane Oxygen Evolution Surface Charge Density Charge Asymmetry Chloroplast Membrane
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