title: Determination of total proton release in purple membrane suspension by umbelliferone fluorescence quenching technique.
abstract: A technique for determining total proton release from purple membrane suspension under steady illumination has been described. Illuminated purple membrane is found to quench the fluorescence life-time of umbelliferone indicating the release of protons in the medium. Besides the "stoichiometric" release of protons from bacteriorhodopsin, there seems to be release of protons from sources other than protonated retinylidene Schiff base moiety also.
authors.affiliation: Department of Chemistry, Indian Institute of Technology, Powai, Bombay.
authors.forename: S
authors.initials: S
authors.lastname: Sonar
authors.forename: A K
authors.initials: AK
authors.lastname: Singh
mesh_terms: D001436:Bacteriorhodopsins / Q000378:metabolism*; D019617:Halobacterium salinarum / Q000378:metabolism; D007700:Kinetics; D008027:Light; D011522:Protons; D013050:Spectrometry, Fluorescence / Q000379:methods; D014468:Umbelliferones
chemical_list: D011522:Protons; D014468:Umbelliferones; D001436:Bacteriorhodopsins; C031477:7-hydroxycoumarin