Biochemistry (Moscow)

, Volume 79, Issue 3, pp 221–226 | Cite as

Mechanism of primary and secondary ion-radical pair formation in photosystem I complexes

  • G. E. Milanovsky
  • V. V. Ptushenko
  • D. A. Cherepanov
  • A. Yu. SemenovEmail author


The mechanisms of the ultrafast charge separation in reaction centers of photosystem I (PS I) complexes are discussed. A kinetic model of the primary reactions in PS I complexes is presented. The model takes into account previously calculated values of redox potentials of cofactors, reorganization energies of the primary P700+A 0 - and secondary P700+A 1 - ion-radical pairs formation, and the possibility of electron transfer via both symmetric branches A and B of redox-cofactors. The model assumes that the primary electron acceptor A0 in PS I is represented by a dimer of chlorophyll molecules Chl2A/Chl3A and Chl2B/Chl3B in branches A and B of the cofactors. The characteristic times of formation of P700+A 0 - and P700+A 1 - calculated on the basis of the model are close to the experimental values obtained by pump-probe femtosecond absorption spectroscopy. It is demonstrated that a small difference in the values of redox potentials between the primary electron acceptors A0A and A0B in branches A and B leads to asymmetry of the electron transfer in a ratio of 70: 30 in favor of branch A. The secondary charge separation is thermodynamically irreversible in the submicrosecond range and is accompanied by additional increase in asymmetry between the branches of cofactors of PS I.

Key words

photosystem I reaction center electron transfer primary reactions kinetic modeling 


A0A and A0B

chlorophyll primary electron acceptor in branches A and B

A1A and A1B

phylloquinone molecules (secondary electron acceptors in branches A and B)



Chl1A/Chl1B, Chl2A/Chl2B, and Chl3A/Chl3B

first, second, and third pairs of chlorophyll molecules in symmetric branches of redox cofactors A and B of PS I


chlorophyll dimer (the primary electron donor)


photosystem I


reaction center


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. 1.
    Sadekar, S., Raymond, J., and Blankenship, R. E. (2006) Mol. Biol. Evol., 23, 2001–2007.PubMedCrossRefGoogle Scholar
  2. 2.
    Jordan, P., Fromme, P., Witt, H. T., Klukas, O., Saenger, W., and Krau Nature, 411, 909–917.Google Scholar
  3. 3.
    Deisenhofer, J., Epp, O., Miki, K., Huber, R., and Michel, H. (1985) Nature, 318, 618–624.PubMedCrossRefGoogle Scholar
  4. 4.
    Komiya, H., Yeates, T. O., Rees, D. C., Allen, J. P., and Feher, G. (1988) Proc. Natl. Acad. Sci. USA, 85, 9012–9016.PubMedCentralPubMedCrossRefGoogle Scholar
  5. 5.
    Guergova-Kuras, M., Boudreaux, B., Joliot, A., Joliot, P., and Redding, K. (2001) Proc. Natl. Acad. Sci. USA, 98, 4437–4442.PubMedCentralPubMedCrossRefGoogle Scholar
  6. 6.
    Srinivasan, N., and Golbeck, J. H. (2009) Biochim. Biophys. Acta Bioenerg., 1787, 1057–1088.CrossRefGoogle Scholar
  7. 7.
    Shelaev, I. V., Gostev, F. E., Mamedov, M. D., Sarkisov, O. M., Nadtochenko, V. A., Shuvalov, V. A., and Semenov, A. Y. (2010) Biochim. Biophys. Acta Bioenerg., 1797, 1410–1420.CrossRefGoogle Scholar
  8. 8.
    Brettel, K. (1988) FEBS Lett., 239, 93–98.CrossRefGoogle Scholar
  9. 9.
    Setif, P., and Bottin, H. (1989) Biochemistry, 28, 2689–2697.CrossRefGoogle Scholar
  10. 10.
    Sauer, K., Mathis, P., Acker, S., and Van Best, J. A. (1978) Biochim. Biophys. Acta, 503, 120–134.PubMedCrossRefGoogle Scholar
  11. 11.
    Vassiliev, I. R., Jung, Y. S., Mamedov, M. D., Semenov, A., and Golbeck, J. H. (1997) Biophys. J., 72, 301–315.PubMedCentralPubMedCrossRefGoogle Scholar
  12. 12.
    Cohen, R. O., Shen, G., Golbeck, J. H., Xu, W., Chitnis, P. R., Valieva, A. I., van der Est, A., Pushkar, Y., and Stehlik, D. (2004) Biochemistry, 43, 4741–4754.PubMedCrossRefGoogle Scholar
  13. 13.
    Dashdorj, N., Xu, W., Cohen, R. O., Golbeck, J. H., and Savikhin, S. (2005) Biophys. J., 88, 1238–1249.PubMedCentralPubMedCrossRefGoogle Scholar
  14. 14.
    Semenov, A. Y., Mamedov, M. D., Golbeck, J. H., Shuvalov, V. A., and Nadtochenko, V. A. (2013) in Abst. Int. Conf. “Photosynthesis Research for Sustainability” (Feyziyev, Y. M., Huseinova, I. M., and Allakhverdiev, S. I., eds.) Nurlar, Baku, p. 79.Google Scholar
  15. 15.
    Savitsky, A., Gopta, O., Mamedov, M., Golbeck, J. H., Tikhonov, A., Moebius, K., and Semenov, A. (2010) Appl. Magnet. Resonance, 37, 85–102.CrossRefGoogle Scholar
  16. 16.
    Cornell, W. D., Cieplak, P., Bayly, C. I., Gould, I. R., Merz, K. M., Ferguson, D. M., Spellmeyer, D. C., Fox, T., Caldwell, J. W., and Kollman, P. A. (1995) J. Am. Chem. Soc., 117, 5179–5197.CrossRefGoogle Scholar
  17. 17.
    Sitkoff, D., Sharp, K. A., and Honig, B. (1994) J. Phys. Chem., 98, 1978–1988.CrossRefGoogle Scholar
  18. 18.
    Ptushenko, V. V., Cherepanov, D. A., Krishtalik, L. I., and Semenov, A. Y. (2008) Photosynth. Res., 97, 55–74.PubMedCrossRefGoogle Scholar
  19. 19.
    Muller, M. G., Niklas, J., Lubitz, W., and Holzwarth, A. R. (2003) Biophys. J., 85, 3899–3922.PubMedCentralPubMedCrossRefGoogle Scholar
  20. 20.
    Marcus, R. A., and Sutin, N. (1985) Biochim. Biophys. Acta, 811, 265–322.CrossRefGoogle Scholar
  21. 21.
    Moser, C. C., and Dutton, P. L. (1992) Biochim. Biophys. Acta, 1101, 171–176.PubMedCrossRefGoogle Scholar
  22. 22.
    Onuchic, J. N., Beratan, D. N., Winkler, J. R., and Gray, H. B. (1992) Annu. Rev. Biophys. Biomol. Struct., 21, 349–377.PubMedCrossRefGoogle Scholar
  23. 23.
    Santabarbara, S., Heathcote, P., and Evans, M. C. W. (2005) Biochim. Biophys. Acta, 1708, 283–310.PubMedCrossRefGoogle Scholar
  24. 24.
    Ishikita, H., and Knapp, E.-W. (2003) J. Biol. Chem., 26, 52002–52011.CrossRefGoogle Scholar
  25. 25.
    Milanovsky, G. E., Ptushenko, V. V., Golbeck, G. H., Semenov, A. Yu., and Cherepanov, D. A. (2014) Biochim. Biophys. Acta, in press.Google Scholar
  26. 26.
    Sigfridsson, E., Olsson, M. H. M., and Ryde, U. (2001) J. Phys. Chem. B, 105, 5546–5552.CrossRefGoogle Scholar
  27. 27.
    Amashukeli, X., Gruhn, N. E., Lichtenberger, D. L., Winkler, J. R., and Gray, H. B. (2004) J. Am. Chem. Soc., 126, 15566–15571.PubMedCrossRefGoogle Scholar
  28. 28.
    Sarkisov, O. M., Gostev, F. E., Shelaev, I. V., Novoderezhkin, V. I., Gopta, O. A., Mamedov, M. D., Semenov, A. Y., and Nadtochenko, V. A. (2006) Phys. Chem. Chem. Phys., 8, 5671–5678.PubMedCrossRefGoogle Scholar
  29. 29.
    Shelaev, I. V., Gostev, F. E., Vishnev, M. I., Shkuropatov, A. Ya., Ptushenko, V. V., Mamedov, M. D., Sarkisov, O. M., Nadtochenko, V. A., Semenov, A. Yu., and Shuvalov, V. A. (2011) J. Photochem. Photobiol. B: Biol., 104, 44–50.CrossRefGoogle Scholar

Copyright information

© Pleiades Publishing, Ltd. 2014

Authors and Affiliations

  • G. E. Milanovsky
    • 1
  • V. V. Ptushenko
    • 1
  • D. A. Cherepanov
    • 2
  • A. Yu. Semenov
    • 1
    Email author
  1. 1.Belozersky Institute of Physico-Chemical BiologyLomonosov Moscow State UniversityMoscowRussia
  2. 2.Frumkin Institute of Physical Chemistry and ElectrochemistryRussian Academy of SciencesMoscowRussia

Personalised recommendations