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Hoffmann, R. A wiki for the life sciences where authorship matters. Nature Genetics (2008)
 
MeSH Review

Purple Membrane

 
 
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High impact information on Purple Membrane

  • Stationary photocurrents, measured with purple membranes immobilized and oriented in a polyacrylamide gel, increased upon addition of azide up to the level of the wild-type [1].
  • We also provide evidence for involvement of the PAS/PAC domain of Bat in redox-sensing activity by genetic analysis of a purple membrane overproducer [2].
  • Purple membranes, selectively labeled by fluorescein at Lys-129 of bacteriorhodopsin, were pulsed by protons released in the aqueous bulk from excited pyranine (8-hydroxy-1,3,6-pyrenetrisulfonate) and the reaction of protons with the indicators was measured [3].
  • Solubilizations of the purple membrane from Halobacterium halobium with the detergent Tritain X-100 followed by gel filtration in deoxycholate solution gave bacteriorhodopsin that was more than 99% free from endogenous lipid [4].
  • Difference Fourier techniques permit a general assessment of the distribution of valine and phenylalanine in projections of the purple membrane structure [5].
 

Biological context of Purple Membrane

  • The decrease in the flash intensity dependence of the M kinetics after different extents of bleaching of the purple membranes by hydroxylamine proves the existence of a cooperative interaction between the photocycling BR molecules [6].
  • Above the lipid-phase transition light adaptation in the monomers, measured as either the red shift of the visible absorbance maximum or the isomerizaiton o 13-cis- to all-trans-retinal, is also reduced to less than half of the extent observed in intact purple membrane or in the bR aggregates formed in lipid vesicles below the plhase transition [7].
  • Other easily detectable phenotypes, like the synthesis of bacterioruberin (Rub) or the synthesis of retinal (Ret) and bacterio-opsin (Ops), the two components which form the purple membrane (Pum) of H. halobium, are lost at a frequency of about 10(-4) [8].
  • Recent studies on the regulation of the bacterio-opsin (bop) gene of the archaebacterium Halobacterium halobium suggest that the brp and putative bat genes are involved in bop gene expression or purple membrane assembly [9].
  • In the wild-type NRC-1 strain, the bop gene, encoding the purple membrane protein bacterio-opsin, is found on the bacterial chromosome, while the gas vesicle protein genes, gvpA and gvpC, are present on pNRC100, a multicopy plasmid of approximately 150 kilobase pairs [10].
 

Anatomical context of Purple Membrane

 

Associations of Purple Membrane with chemical compounds

  • The trimeric bacteriorhodopsin in papain-treated purple membrane dissociates into monomers in Triton X-100 which, after removal of the detergent, reassociate to form the oligomeric structures [15].
  • The specific activity and kinetic parameters Km and Vmax of phospholipase D for the purple membrane phospholipid are similar to those for egg phosphatidylcholine [16].
  • When the major polar lipid of purple membrane, a dialkyl analogue of phosphatidyl glycerophosphate, is treated with phospholipase D under the usual assay conditions for this enzyme, the reaction yields dialkylglycerol and glycerol bisphosphate, i.e. the kind of products that would be expected from a phospholipase C reaction [16].
  • A series of stearic acid spin labels bound to purple membranes was used to define the depth of paramagnetic interactions [17].
  • BR in Triton X-100 or nonylglucoside, delipidated BR in CHAPSO, and BR in intact purple membrane all have a dark-adapted ratio of 13-cis to all-trans-retinal of 1.9:1 [18].
 

Gene context of Purple Membrane

  • The bop promoter expressed HR to an extent where a specific membrane fraction resembled the crystalline purple membrane of BR in terms of the lipid to protein ratio [19].
  • The maximum stoichiometry was 10 mol/mol of bacteriorhodopsin, which is close to the amount of phospholipid phosphorus in purple membrane [20].
  • The deuterated hydration shells of bovine serum (BSA) albumin, and purple membrane sheets have been studied by the aid of deuteron field-cycling relaxation spectroscopy [21].
  • When the temperature was raised from 10 to 35 degrees C, Dw in all membranes increased approximately 3-fold, corresponding to activation energies of 7-8 kcal/mol, and theta c increased by about 10 degrees, except for the purple membrane in which the angular range remained narrow [22].
  • Reliability of phases retrieved from 400-kV spot-scan images of purple membranes acquired on a slow-scan CCD camera [23].
 

Analytical, diagnostic and therapeutic context of Purple Membrane

References

  1. A defective proton pump, point-mutated bacteriorhodopsin Asp96----Asn is fully reactivated by azide. Tittor, J., Soell, C., Oesterhelt, D., Butt, H.J., Bamberg, E. EMBO J. (1989) [Pubmed]
  2. Genomic and genetic dissection of an archaeal regulon. Baliga, N.S., Kennedy, S.P., Ng, W.V., Hood, L., DasSarma, S. Proc. Natl. Acad. Sci. U.S.A. (2001) [Pubmed]
  3. Protonation dynamics of the extracellular and cytoplasmic surface of bacteriorhodopsin in the purple membrane. Nachliel, E., Gutman, M., Kiryati, S., Dencher, N.A. Proc. Natl. Acad. Sci. U.S.A. (1996) [Pubmed]
  4. Delipidation of bacteriorhodopsin and reconstitution with exogenous phospholipid. Huang, K.S., Bayley, H., Khorana, H.G. Proc. Natl. Acad. Sci. U.S.A. (1980) [Pubmed]
  5. Bacteriorhodopsin is an inside-out protein. Engelman, D.M., Zaccai, G. Proc. Natl. Acad. Sci. U.S.A. (1980) [Pubmed]
  6. Dimeric-like kinetic cooperativity of the bacteriorhodopsin molecules in purple membranes. Tokaji, Z. Biophys. J. (1993) [Pubmed]
  7. Effect of protein-protein interaction on light adaptation of bacteriorhodopsin. Casadio, R., Stoeckenius, W. Biochemistry (1980) [Pubmed]
  8. Genetic variability in Halobacterium halobium. Pfeifer, F., Weidinger, G., Goebel, W. J. Bacteriol. (1981) [Pubmed]
  9. Transcription of genes involved in bacterio-opsin gene expression in mutants of a halophilic archaebacterium. Leong, D., Boyer, H., Betlach, M. J. Bacteriol. (1988) [Pubmed]
  10. Mechanisms of genetic variability in Halobacterium halobium: the purple membrane and gas vesicle mutations. DasSarma, S. Can. J. Microbiol. (1989) [Pubmed]
  11. Molecular orientation of bacteriorhodopsin within the purple membrane of Halobacterium halobium. Hayward, S.B., Grano, D.A., Glaeser, R.M., Fisher, K.A. Proc. Natl. Acad. Sci. U.S.A. (1978) [Pubmed]
  12. Infrared spectroscopic study of photoreceptor membrane and purple membrane. Protein secondary structure and hydrogen deuterium exchange. Downer, N.W., Bruchman, T.J., Hazzard, J.H. J. Biol. Chem. (1986) [Pubmed]
  13. Does bacteriorhodopsin energize the membranes of animal mitochondria under light? Okon, E.B., Vsevolodov, N.N. FEBS Lett. (1987) [Pubmed]
  14. Retained activities of some membrane proteins in stable lipid bilayers on a solid support. Puu, G., Gustafson, I., Artursson, E., Ohlsson, P.A. Biosensors & bioelectronics. (1995) [Pubmed]
  15. Removal of the carboxyl-terminal peptide does not affect refolding or function of bacteriorhodopsin as a light-dependent proton pump. Liao, M.J., Khorana, H.G. J. Biol. Chem. (1984) [Pubmed]
  16. Release of dialkylglycerol from purple membrane phospholipids by phospholipase D. Muga, A., Arrondo, J.L., Gurtubay, J.I., Goñi, F.M. J. Biol. Chem. (1990) [Pubmed]
  17. Topographic studies of spin-labeled bacteriorhodopsin. Evidence for buried carboxyl residues and immobilization of the COOH-terminal tail. Herz, J.M., Mehlhorn, R.J., Packer, L. J. Biol. Chem. (1983) [Pubmed]
  18. Purification of bacteriorhodopsin and characterization of mature and partially processed forms. Miercke, L.J., Ross, P.E., Stroud, R.M., Dratz, E.A. J. Biol. Chem. (1989) [Pubmed]
  19. Homologous overexpression of a light-driven anion pump in an archaebacterium. Heymann, J.A., Havelka, W.A., Oesterhelt, D. Mol. Microbiol. (1993) [Pubmed]
  20. Charge asymmetry of the purple membrane measured by uranyl quenching of dansyl fluorescence. Renthal, R., Cha, C.H. Biophys. J. (1984) [Pubmed]
  21. Deuteron field-cycling relaxation spectroscopy and translational water diffusion in protein hydration shells. Schauer, G., Kimmich, R., Nusser, W. Biophys. J. (1988) [Pubmed]
  22. Dynamic structure of biological membranes as probed by 1,6-diphenyl-1,3,5-hexatriene: a nanosecond fluorescence depolarization study. Kinosita, K., Kataoka, R., Kimura, Y., Gotoh, O., Ikegami, A. Biochemistry (1981) [Pubmed]
  23. Reliability of phases retrieved from 400-kV spot-scan images of purple membranes acquired on a slow-scan CCD camera. Sherman, M.B., Chiu, W. Journal of microscopy. (1997) [Pubmed]
  24. Bacteriorhodopsin precursor is processed in two steps. Wölfer, U., Dencher, N.A., Büldt, G., Wrede, P. Eur. J. Biochem. (1988) [Pubmed]
  25. Altered protein-chromophore interaction in dicyclohexylcarbodiimide-modified purple membrane sheets. Renthal, R., Brogley, L., Vila, J. Biochim. Biophys. Acta (1988) [Pubmed]
 
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