Abstract
Proton pumping in closed vesicular systems containing bacteriorhodopsin that is initiated by an orange flash, is diminished by a subsequent blue flash. This blue light effect is due to light absorbed by the photocycle intermediate M412 (M), which was formed by the orange flash. A kinetic analysis of the blue-light-induced reduction of proton pumping shows that of the two components of M, only the slowly decaying component is involved in the reduction of proton movement. This may be the first correlation between a proton movement and a specific photochemical intermediate of bacteriorhodopsin. Furthermore, we report that blue light, acting on the slowly decaying intermediate, probably causes a movement of the protons in a direction opposite to that normally seen for light absorbed by bacteriorhodopsin.
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- Becher B. M., Cassim J. Y. Improved isolation procedures for the purple membrane of Halobacterium halobium. Prep Biochem. 1975;5(2):161–178. doi: 10.1080/00327487508061568. [DOI] [PubMed] [Google Scholar]
- Becher B., Ebrey T. G. The quantum efficiency for the photochemical conversion of the purple membrane protein. Biophys J. 1977 Feb;17(2):185–191. doi: 10.1016/S0006-3495(77)85636-1. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Dancsházy Z., Drachev L. A., Ormos P., Nagy K., Skulachev V. P. Kinetics of the blue light-induced inhibition of photoelectric activity of bacteriorhodopsin. FEBS Lett. 1978 Dec 1;96(1):59–63. doi: 10.1016/0014-5793(78)81062-x. [DOI] [PubMed] [Google Scholar]
- Govindjee R., Ebrey T. G., Crofts A. R. The quantum efficiency of proton pumping by the purple membrane of Halobacterium halobium. Biophys J. 1980 May;30(2):231–242. doi: 10.1016/S0006-3495(80)85091-0. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Hess B. Technology of biomolecular design, with experiments on light control of the photochemical cycle in Halobacterium halobium. FEBS Lett. 1976 Apr 15;64(1):26–28. doi: 10.1016/0014-5793(76)80240-2. [DOI] [PubMed] [Google Scholar]
- Kalisky O., Ottolenghi M., Honig B., Korenstein R. Environmental effects on formation and photoreaction of the M412 photoproduct of bacteriorhodopsin: implications for the mechanism of proton pumping. Biochemistry. 1981 Feb 3;20(3):649–655. doi: 10.1021/bi00506a031. [DOI] [PubMed] [Google Scholar]
- Lozier R. H., Niederberger W., Bogomolni R. A., Hwang S., Stoeckenius W. Kinetics and stoichiometry of light-induced proton release and uptake from purple membrane fragments, Halobacterium halobium cell envelopes, and phospholipid vesicles containing oriented purple membrane. Biochim Biophys Acta. 1976 Sep 13;440(3):545–556. doi: 10.1016/0005-2728(76)90041-4. [DOI] [PubMed] [Google Scholar]
- MacDonald R. E., Lanyi L. K. Light-induced leucine transport in Halobacterium halobium envelope vesicles: a chemiosmotic system. Biochemistry. 1975 Jul;14(13):2882–2889. doi: 10.1021/bi00684a014. [DOI] [PubMed] [Google Scholar]
- Oesterhelt D., Hess B. Reversible photolysis of the purple complex in the purple membrane of Halobacterium halobium. Eur J Biochem. 1973 Aug 17;37(2):316–326. doi: 10.1111/j.1432-1033.1973.tb02990.x. [DOI] [PubMed] [Google Scholar]
- Ormos P., Dancsházy Z., Karvaly B. Mechanism of generation and regulation of photopotential by bacteriorhodopsin in bimolecular lipid membrane. Biochim Biophys Acta. 1978 Aug 8;503(2):304–315. doi: 10.1016/0005-2728(78)90190-1. [DOI] [PubMed] [Google Scholar]
- Ort D. R., Parson W. W. Flash-induced volume changes of bacteriorhodopsin-containing membrane fragments and their relationship to proton movements and absorbance transients. J Biol Chem. 1978 Sep 10;253(17):6158–6164. [PubMed] [Google Scholar]
- Stoeckenius W., Lozier R. H., Bogomolni R. A. Bacteriorhodopsin and the purple membrane of halobacteria. Biochim Biophys Acta. 1979 Mar 14;505(3-4):215–278. doi: 10.1016/0304-4173(79)90006-5. [DOI] [PubMed] [Google Scholar]