Biochemistry (Moscow)

, Volume 73, Issue 1, pp 107–111 | Cite as

Study of redox potential in cytochrome c covalently bound to terminal oxidase of alkaliphilic Bacillus pseudofirmus FTU

Article

Abstract

Spectroelectrochemistry was used to determine the midpoint redox potentials of heme cofactors of the caa 3-type cytochrome oxidase from the alkaliphilic bacterium Bacillus pseudofirmus FTU. The apparent midpoint potentials (E m app ) for the most prominent transitions of hemes a and a 3 (+193 and +334 mV, respectively) were found to be similar to the values reported for other enzymes with high homology to the caa 3-type oxidase. In contrast, the midpoint potential of the covalently bound cytochrome c (+89 mV) was 150–170 mV lower than in cytochromes c, either low molecular weight or covalently bound to the caa 3 complex in all known aerobic neutralophilic and thermo-neutralophilic bacteria. Such an unusually low redox potential of the covalently bound cytochrome c of the caa 3-type oxidase of alkaliphilic bacteria, together with high redox potentials of hemes a and a 3, ensures more than twice higher difference in redox potentials inside the respiratory complex compared to the homologous mitochondrial enzyme. The energy released during this redox transition might be stored in the transmembrane H+ gradient even under low Δp in the alkaline environment of the bacteria at the expense of a significant increase in ΔG of the coupled redox reaction.

Key words

Bacillus pseudofirmus alkaliphile cytochrome c caa3 cytochrome oxidase redox potential 

Abbreviations

OG

n-octyl-β-D-glucopyranoside

Δp

proton motive force

ΔG

free energy of the reaction

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References

  1. 1.
    Tsukihara, T., Aoyama, H., Yamashita, E., Takashi, T., Yamaguchi, H., Shinzawa-Itoh, K., Nakashima, R., Yaono, R., and Yoshikawa, S. (1996) Science, 272, 1136–1144.CrossRefPubMedGoogle Scholar
  2. 2.
    Yoshikawa, S., Shinzawa-Itoh, K., Nakashima, R., Yaono, R., Inoue, N., Yao, M., Fei, M. J., Libeu, C. P., Mizushima, T., Yamaguchi, H., Tomizaki, T., and Tsukihara, T. (1998) Science, 280, 1723–1729.CrossRefPubMedGoogle Scholar
  3. 3.
    Iwata, S., Ostermeier, C., Ludwig, B., and Michel, H. (1995) Nature, 376, 660–669.CrossRefPubMedGoogle Scholar
  4. 4.
    Ostermeier, C., Harrenga, A., Ermler, U., and Michel, H. (1997) Proc. Natl. Acad. Sci. USA, 94, 10547–10553.CrossRefPubMedGoogle Scholar
  5. 5.
    Svensson-Ek, M., Abramson, J., Larsson, G., Tornroth, S., Brzezinski, P., and Iwata, S. (2002) J. Mol. Biol., 321, 329–339.CrossRefPubMedGoogle Scholar
  6. 6.
    Pereira, M. M., Santana, M., and Teixeira, M. (2001) Biochim. Biophys. Acta, 1505, 185–208.CrossRefPubMedGoogle Scholar
  7. 7.
    Krulwich, T. A., Ito, M., Gilmour, R., Sturr, M. G., Guffanti, A. A., and Hicks, D. B. (1996) Biochim. Biophys. Acta, 1275, 21–26.CrossRefPubMedGoogle Scholar
  8. 8.
    Sone, N., Ogura, T., Noguchi, S., and Kitagawa, T. (1994) Biochemistry, 33, 849–855.CrossRefPubMedGoogle Scholar
  9. 9.
    Yumoto, I., Takahashi, S., Kitagawa, T., Fukumori, Y., and Yamanaka, T. (1993) J. Biochem., 114, 88–95.PubMedGoogle Scholar
  10. 10.
    Yumoto, I. (2002) J. Biosci. Bioeng., 93, 342–353.PubMedGoogle Scholar
  11. 11.
    Muntyan, M. S., and Skripnikova, E. V. (1993) Biochemistry (Moscow), 58, 928–933.Google Scholar
  12. 12.
    Moura, J. J. G., Costa, C., Liu, M.-Y., Moura, I., and LeGall, J. (1991) Biochim. Biophys. Acta, 1058, 61–66.CrossRefPubMedGoogle Scholar
  13. 13.
    Orii, Y., Yumoto, I., Fukumori, Y., and Yamanaka, T. (1991) J. Biol. Chem., 266, 14310–14316.PubMedGoogle Scholar
  14. 14.
    Grischuk, Y. V., Muntyan, M. S., Popova, I. V., and Sorokin, D. Y. (2003) Biochemistry (Moscow), 68, 385–390.CrossRefGoogle Scholar
  15. 15.
    Lewis, R. J., Prince, R. C., Dutton, P. L., Knaff, D. B., and Krulwich, T. A. (1981) J. Biol. Chem., 256, 10543–10549.PubMedGoogle Scholar
  16. 16.
    Pereira, M. M., Carita, J. N., and Teixeira, M. (1999) Biochemistry, 38, 1268–1275.CrossRefPubMedGoogle Scholar
  17. 17.
    Poole, R. K. (1983) Biochim. Biophys. Acta, 726, 205–243.PubMedGoogle Scholar
  18. 18.
    Hellwig, P., Soulimane, T., and Mantele, W. (2002) Eur. J. Biochem., 269, 4830–4838.CrossRefPubMedGoogle Scholar
  19. 19.
    Hicks, D. B., and Krulwich, T. A. (1995) Biochim. Biophys. Acta, 1229, 303–314.CrossRefPubMedGoogle Scholar

Copyright information

© Pleiades Publishing, Ltd. 2008

Authors and Affiliations

  1. 1.Belozersky Institute of Physico-Chemical BiologyLomonosov Moscow State UniversityMoscowRussia
  2. 2.Institute of BiotechnologyUniversity of HelsinkiHelsinkiFinland

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