Surface Charge Density Changes in Isolated Photosystem II Membranes Induced by Depletion of the Extrinsic Polypeptides of the Oxygen Evolving System
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چکیده
Treatment of PS II particles with either 1 m NaCl or alkaline Tris (1 m , pH 8.4) caused a considerable decrease in the average net negative surface charge density, concomitant with de pletion of the extrinsic 17, 24 and 33 kDa proteins of the oxygen evolving complex from the membranes. The partial recovery of the values for surface charge in both NaCland Tris-treated membranes was registered after reconstitution experiments with the three proteins. These results are compared with the data for the charge densities of the thylakoid membranes, to examine the role of the three extrinsic proteins in the formation of heterogeneous arrangement of surface charge across the appressed (granal) thylakoids.
منابع مشابه
Purification and properties of an oxygen-evolving reaction center complex from photosystem II membranes A simple procedure utilizing a non-ionic detergent and elevated ionic strength
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