Application of Chemical Modification and Spin Labeling Techniques to the Study of Energy Conversion by Bacteriorhodopsin
Light generates a pH gradient and an electrical potential across the purple membrane of Halobacterium halobium. We are investigating the time resolved changes in protonation of the side chains of specific amino acid residues and the correlation of these changes with photon absorption and the ensuing photo-reaction cycle. We seek to determine the precise molecular description of the photocycle and of the time dependent steps in the uptake, translocation, and release of protons by the retinal proton catalyst in this membrane, bacteriorhodopsin (BR).
KeywordsSchiff Base Purple Membrane Proton Release Proton Movement Photostationary State
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