Journal of Bioenergetics and Biomembranes

, Volume 23, Issue 2, pp 365–379 | Cite as

Functional characterization of the lesion in the ubiquinol: Cytochromec oxidoreductase complex isolated from the nonphotosynthetic strain R126 ofRhodobacter capsulatus

  • Javier G. Fernández-Velasco
  • Silvia Cocchi
  • Mauro Neri
  • Günter Hauska
  • B. Andrea Melandri
Research Articles


The cytochromebc1 complexes from the nonphotosynthetic strain R126 ofRhodobacter capsulatus and from its revertant MR126 were purified. Between both preparations, no difference could be observed in the stoichiometries of the cytochromes, in their spectral properties, and in their midpoint redox potentials. Both also showed identical polypeptide patterns after electrophoresis on polyacrylamide gels in the presence of sodium dodecylsulfate. The ubiquinol: cytochromec oxidoreductase activity was strongly inhibited in the complex from the mutant compared to the one from the revertant. So was the oxidant-induced extra reduction of cytochromeb. Both preparations, however, showed an antimycin-induced red shift of cytochromeb, as well as antimycin-sensitive reduction of cytochromeb by ubiquinol. In accordance with a preceding study of chromatophores (Robertsonet al. (1986).J. Biol. Chem.261, 584–591), it is concluded that the mutation affects specifically the ubiquinol oxidizing site, leaving the ubiquinol reducing site unchanged.

Key Words

Cytochromebc1 complex ubiquinol oxidation ubiquinone reduction electron transport Rhodobacter capsulatus photosynthetic bacteria 


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. Andrews, K. M., Crofts, A. R., and Gennis, R. B. (1990).Biochemistry 29, 2645–2651.Google Scholar
  2. Clayton, R. K. (1963).Biochim. Biophys. Acta 75, 312–323.Google Scholar
  3. Crane, F. L., and Barr, R. (1971).Methods Enzymol. 18C, 137–165.Google Scholar
  4. Crofts, A. R., and Wraight, C. A. (1983).Biochim. Biophys. Acta 726, 149–185.Google Scholar
  5. Crofts, A. R., Meinhardt, S. W., Jones, K. R., and Snozzi, M. (1983).Biochim. Biophys. Acta 723, 202–218.Google Scholar
  6. Daldal, F., Tokito, M. K., Davidson, E., and Faham, M. (1989).EMBO J. 8, 3951–3961.Google Scholar
  7. Drews, G. (1985).Microbiol. Rev. 49, 59–70.Google Scholar
  8. Dutton, P. L., and Prince, R. C. (1978). In:The Photosynthetic Bacteria (Clayton, R. K., and Sistrom, W. R., eds.), Plenum Press, New York, pp. 525–570.Google Scholar
  9. Fernández-Velasco, J. G., Neri, M., Cocchi, S., Hauska, G., and Melandri, B. A. (1986).4th Eur. Bioenerg. Confer., short reports, Congress Edition, Prague, p. 119.Google Scholar
  10. Gabellini, N. (1988).J. Bioenerg, Biomembr. 20, 59–83.Google Scholar
  11. Gabellini, N., and Hauska, G. (1983).FEBS Lett. 153, 146–150.Google Scholar
  12. Gabellini, N., and Sebald, W. (1986).Eur. J. Biochem. 154, 569–579.Google Scholar
  13. Gabellini, N., and Bowyer, J. R., Hurt, E., Melandri, B. A., and Hauska, G. (1982).Eur. J. Biochem. 126, 101–111.Google Scholar
  14. Gabellini, N., Harnisch, U., McCarthy, J. E. G., Hauska, G., and Sebald, W. (1985).EMBO J. 4, 549–553.Google Scholar
  15. García, A. F., Venturoli, G., Gad'on, N., Fernández-Velasco, J. G., Melandri, B. A., and Drews, G. (1987).Biochim. Biophys. Acta 890, 335–345.Google Scholar
  16. Glaser, E. G., Meinhardt, S. W., and Crofts, A. R. (1984).FEBS Lett. 178, 336–342.Google Scholar
  17. Hauska, G. (1986).Methods Enzymol. 126, 271–285.Google Scholar
  18. Hauska, G., Hurt, E., Gabellini, N., and Lockau, W. (1983).Biochim. Biophys. Acta 726, 97–133.Google Scholar
  19. Laemmli, U. K. (1970).Nature (London)227, 680–685.Google Scholar
  20. Link, T., and von Jagow, G. (1986).Methods Enzymol. 126, 253–271.Google Scholar
  21. Ljungdahl, P. O., Pennoyer, J. D., and Trumpower, B. L. (1986).Methods Enzymol. 126, 181–191.Google Scholar
  22. Lowry, O. H., Rosebrough, N. J., Farr, A. L., and Randall, R. J. (1951).J. Biol. Chem. 193, 265–275.Google Scholar
  23. Marrs, B. L. (1978).Curr. Top. Bioenerg. 8, 261–294.Google Scholar
  24. Marrs, B. L., Stahl, C. L., Lien, S., and Gest, H. (1972).Proc. Natl. Acad. Sci. USA 69, 916–920.Google Scholar
  25. Matsuura, K., Bowyer, J. R., Ohnishi, T., and Dutton, P. L. (1983).J. Biol. Chem. 258, 1571–1579.Google Scholar
  26. Meinhardt, S. W., and Crofts, A. R. (1982).FEBS Lett. 149, 217–222.Google Scholar
  27. Melandri, B. A., and Venturoli, G. (1984). InBioenergetics (Ernster, L., ed.), Elsevier, Amsterdam, pp. 95–148.Google Scholar
  28. Mitchell, P. (1976).J. Theor. Biol. 62, 327–367.Google Scholar
  29. Ormerod, J. G., Ormerod, K. S., and Gest, H. (1961).Arch. Biochem. Biophys. 94, 449–456.Google Scholar
  30. Purvis, D. J., Theiler, R., and Niederman, R. A. (1990).J. Biol. Chem. 265, 1208–1215.Google Scholar
  31. Rieske, J. S. (1967).Methods Enzymol. 10, 239–245.Google Scholar
  32. Robertson, D. E., and Dutton, P. L. (1988).Biochim. Biophys. Acta 935, 273–291.Google Scholar
  33. Robertson, D. E., Giangiacomo, K. M., De Vries, S., Moser, C. C., and Dutton, P. L. (1984).FEBS Lett. 178, 343–350.Google Scholar
  34. Robertson, D. E., Davidson, E., Prince, R. C., van den Berg, W. H., Marrs, B. L., and Dutton, P. L. (1986).J. Biol. Chem. 261, 584–591.Google Scholar
  35. Takamiya, K., Doi, M., and Okimatsu, H. (1982).Plant Cell. Physiol. 23, 987–997.Google Scholar
  36. Thomas, P. E., Ryan, D., and Wayne, L. (1976).Anal. Biochem. 75, 168–176.Google Scholar
  37. Venturoli, G., Fernández-Velasco, J. G., Crofts, A. R., and Melandri, B. A. (1986).Biochim. Biophys. Acta 851, 340–352.Google Scholar
  38. Venturoli, G., Fernández-Velasco, J. G., Crofts, A. R., and Melandri, B. A. (1988).Biochim. Biophys. Acta 935, 258–272.Google Scholar
  39. von Jagow, G., and Engel, W. D. (1981).FEBS Lett. 136, 19–24.Google Scholar
  40. Wikström, M., and Krab, K. (1986).J. Bioenerg. Biomembr. 18, 181–193.Google Scholar
  41. Wood, P. M. (1980).Biochem. J. 189, 385–391.Google Scholar
  42. Yu, L., and Yu, C-A. (1987).Biochemistry 26, 3658–3664.Google Scholar
  43. Yu, L., Mei, Q-C., and Yu, C-A. (1984).J. Biol. Chem. 259, 5752–5760.Google Scholar
  44. Zannoni, D., and Marrs, B. L. (1981).Biochim. Biophys. Acta 637, 96–106.Google Scholar

Copyright information

© Plenum Publishing Corporation 1991

Authors and Affiliations

  • Javier G. Fernández-Velasco
    • 1
  • Silvia Cocchi
    • 1
  • Mauro Neri
    • 1
  • Günter Hauska
    • 2
  • B. Andrea Melandri
    • 1
  1. 1.Istituto ed Orto BotanicoUniversità di BolognaBolognaItaly
  2. 2.Institut fuer Zellbiologie und PflanzenphysiologieUniversitaet RegensburgRegensburgGermany

Personalised recommendations