Skip to main content
PMC home page
The EMBO Journal logoLink to The EMBO Journal
. 1986 Apr;5(4):805–811. doi: 10.1002/j.1460-2075.1986.tb04285.x

Evidence for light-induced 13-cis, 14-s-cis isomerization in bacteriorhodopsin obtained by FTIR difference spectroscopy using isotopically labelled retinals

Klaus Gerwert 1,1, Friedrich Siebert 1
PMCID: PMC1166862  PMID: 16453681

Abstract

We have obtained by Fourier transformed infra-red (FTIR)-spectroscopy BR-K, BR-L and BR-M difference spectra of bacteriorhodopsin regenerated with isotopically labelled retinals. Thereby, we are able to assign reliably the C14–C15 and C=N stretching vibrations of the various intermediates. The lower C14–C15 stretching vibration frequency in L as compared with 13-cis protonated Schiff base model compounds indicates a 13-cis, 14-s-cis configuration of the retinal in this species. The unusually low C=N stretching vibration in K at 1615 cm−1 indicates less stabilization of the positive charge at the Schiff base by the protein environment. Based on these results, a mechanism is suggested by which the stored light energy is transformed into proton transfers.

Keywords: FTIR, bacteriorhodopsin, vibrational analysis, proton pump mechanism, retinal isotopic derivatives

Full text

PDF
808

Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. Braiman M., Mathies R. Resonance Raman evidence for an all-trans to 13-cis isomerization in the proton-pumping cycle of bacteriorhodopsin. Biochemistry. 1980 Nov 11;19(23):5421–5428. doi: 10.1021/bi00564a042. [DOI] [PubMed] [Google Scholar]
  2. Engelhard M., Gerwert K., Hess B., Kreutz W., Siebert F. Light-driven protonation changes of internal aspartic acids of bacteriorhodopsin: an investigation by static and time-resolved infrared difference spectroscopy using [4-13C]aspartic acid labeled purple membrane. Biochemistry. 1985 Jan 15;24(2):400–407. doi: 10.1021/bi00323a024. [DOI] [PubMed] [Google Scholar]
  3. Oesterhelt D., Stoeckenius W. Functions of a new photoreceptor membrane. Proc Natl Acad Sci U S A. 1973 Oct;70(10):2853–2857. doi: 10.1073/pnas.70.10.2853. [DOI] [PMC free article] [PubMed] [Google Scholar]
  4. Oesterhelt D., Stoeckenius W. Isolation of the cell membrane of Halobacterium halobium and its fractionation into red and purple membrane. Methods Enzymol. 1974;31:667–678. doi: 10.1016/0076-6879(74)31072-5. [DOI] [PubMed] [Google Scholar]
  5. Rothschild K. J., Roepe P., Lugtenburg J., Pardoen J. A. Fourier transform infrared evidence for Schiff base alteration in the first step of the bacteriorhodopsin photocycle. Biochemistry. 1984 Dec 4;23(25):6103–6109. doi: 10.1021/bi00320a031. [DOI] [PubMed] [Google Scholar]
  6. Schulten K., Tavan P. A mechanism for the light-driven proton pump of Halobacterium halobium. Nature. 1978 Mar 2;272(5648):85–86. doi: 10.1038/272085a0. [DOI] [PubMed] [Google Scholar]
  7. Siebert F., Mäntele W. Investigation of the primary photochemistry of bacteriorhodopsin by low-temperature Fourier-transform infrared spectroscopy. Eur J Biochem. 1983 Feb 15;130(3):565–573. doi: 10.1111/j.1432-1033.1983.tb07187.x. [DOI] [PubMed] [Google Scholar]
  8. Smith S. O., Lugtenburg J., Mathies R. A. Determination of retinal chromophore structure in bacteriorhodopsin with resonance Raman spectroscopy. J Membr Biol. 1985;85(2):95–109. doi: 10.1007/BF01871263. [DOI] [PubMed] [Google Scholar]
  9. Smith S. O., Myers A. B., Mathies R. A., Pardoen J. A., Winkel C., van den Berg E. M., Lugtenburg J. Vibrational analysis of the all-trans retinal protonated Schiff base. Biophys J. 1985 May;47(5):653–664. doi: 10.1016/S0006-3495(85)83961-8. [DOI] [PMC free article] [PubMed] [Google Scholar]
  10. Smith S. O., Myers A. B., Pardoen J. A., Winkel C., Mulder P. P., Lugtenburg J., Mathies R. Determination of retinal Schiff base configuration in bacteriorhodopsin. Proc Natl Acad Sci U S A. 1984 Apr;81(7):2055–2059. doi: 10.1073/pnas.81.7.2055. [DOI] [PMC free article] [PubMed] [Google Scholar]
  11. Stockburger M., Klusmann W., Gattermann H., Massig G., Peters R. Photochemical cycle of bacteriorhodopsin studied by resonance Raman spectroscopy. Biochemistry. 1979 Oct 30;18(22):4886–4900. doi: 10.1021/bi00589a017. [DOI] [PubMed] [Google Scholar]
  12. Tavan P., Schulten K., Oesterhelt D. The effect of protonation and electrical interactions on the stereochemistry of retinal schiff bases. Biophys J. 1985 Mar;47(3):415–430. doi: 10.1016/S0006-3495(85)83933-3. [DOI] [PMC free article] [PubMed] [Google Scholar]
  13. Tokunaga F., Ebrey T. The blue membrane: the 3-dehydroretinal-based artificial pigment of the purple membrane. Biochemistry. 1978 May 16;17(10):1915–1922. doi: 10.1021/bi00603a018. [DOI] [PubMed] [Google Scholar]
  14. Warshel A., Russell S. T. Calculations of electrostatic interactions in biological systems and in solutions. Q Rev Biophys. 1984 Aug;17(3):283–422. doi: 10.1017/s0033583500005333. [DOI] [PubMed] [Google Scholar]
  15. Watts T. H., Kay C. M., Paranchych W. Spectral properties of three quaternary arrangements of Pseudomonas pilin. Biochemistry. 1983 Jul 19;22(15):3640–3646. doi: 10.1021/bi00284a016. [DOI] [PubMed] [Google Scholar]

Articles from The EMBO Journal are provided here courtesy of Nature Publishing Group

RESOURCES