Letter | Published:

Light isomerizes the chromophore of bacteriorhodopsin

Abstract

The primary photochemical event in the two light-transducing pigments whose chromophore is retinal, rhodopsin or bacteriorhodopsin, is a source of controversy. It was originally proposed that the primary photoevent in the bleaching of rhodopsin is the photoisomerization of the chromophore from 11-cis to all-trans retinal1,2. Photochemical considerations suggested that a photoisomerization is the primary event in both rhodopsin and bacteriorhodopsin3–7. However, this description of bacteriorhodopsin's photochemistry has been questioned8–10. To elucidate this problem, we determined the isomeric conformation of retinal for two of the photolytic intermediates of bacteriorhodopsin, using a method that enables us to extract chromophores from the photocycle intermediates L and M at low temperatures (−74 °C), and have determined the isomeric conformation of the extracted retinals by HPLC11,12. Here we provide direct evidence that isomerization of the chromophore has taken place in two of the early photocycle intermediates (L and M) of bacteriorhodopsin.

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References

  1. 1

    Kropf, A. & Hubbard, R. Ann. N.Y. Acad. Sci. 74, 266–280 (1958).

  2. 2

    Yoshizawa, T. & Wald, G. Nature 197, 1279–1286 (1963).

  3. 3

    Rosenfeld, T., Honig, B., Ottolenghi, M., Hurley, J. & Ebrey, T. G. Pure appl. Chem. 49, 341–351 (1977).

  4. 4

    Hurley, J., Ebrey, T., Honig, B. & Ottolenghi, M. Nature 270, 540–542 (1977).

  5. 5

    Hurley, J., Becher, B. & Ebrey, T. G. Nature 272, 87–88 (1978).

  6. 6

    Honig, B., Ebrey, T., Callender, R. H., Dinur, U. & Ottolenghi, M. Proc. natn. Acad. Sci. U.S.A. 76, 2503–2507 (1979).

  7. 7

    Mao, B., Ebrey, T. G. & Crouch, R. Biophys. J. 29, 247–250 (1980).

  8. 8

    Applebury, M. L., Peters, K. S. & Rentzepis, P. M. Biophys. J. 23, 375–382 (1978).

  9. 9

    Lewis, A. Proc. natn. Acad. Sci. U.S.A. 75, 549–553 (1978).

  10. 10

    Warshel, A. Proc. natn. Acad. Sci. U.S.A. 75, 2558–2562 (1978).

  11. 11

    Pettei, M. J., Yudd, A. P., Nakanishi, K., Henselman, R. & Stoeckenius, W. Biochemistry 16, 1955–1959 (1977).

  12. 12

    Tsuda, M. & Ebrey, T. G. Biophys. J. 30, 149–158 (1980).

  13. 13

    Stoeckenius, W., Lozier, R. & Bogomolni, R. Biochim. biophys. Acta 505, 212–278 (1979).

  14. 14

    Oesterhelt, D. & Hess, B. Eur. J. Biochem. 37, 316–326 (1973).

  15. 15

    Maeda, A., Iwasa, T. & Yoshizawa, T. J. Biochem. 82, 1599–1604 (1977).

  16. 16

    Ohno, K., Takeuchi, Y. & Yoshida, M. J. Biochem. 82, 1177–1180 (1977).

  17. 17

    Sperling, W., Carl, P., Rafferty, Ch.N. & Dencher, N. A. Biophys. struct. Mech. 3, 79–94 (1977).

  18. 18

    Aton, B., Doukas, A. G., Callender, R. H., Becher, B. & Ebrey, T. G. Biochim. biophys. Acta 576, 424–428 (1979).

  19. 19

    Tokunaga, F., Iwasa, T. & Yoshizawa, T. FEBS Lett. 72, 33–38 (1976).

  20. 20

    Becher, B., Tokunaga, F. & Ebrey, T. G. Biochemistry 17, 2293–2300 (1978).

  21. 21

    Iwasa, T., Tokunaga, F. & Yoshizawa, T. Biophys. struct. Mech. (in the press).

  22. 22

    Aton, B., Doukas, A. G., Callender, R. H., Becher, B. & Ebrey, T. G. Biochemistry 16, 2995–2999 (1979).

  23. 23

    Stockburger, M., Klosmann, W., Guttermann, H., Massing, G. & Peters, R. Biochemistry 18, 4886–4900 (1979).

  24. 24

    Hubbard, R. J. Am. chem. Soc. 78, 4662–4665 (1965).

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