Photosynthesis Research

, Volume 61, Issue 3, pp 253–267 | Cite as

Laser-flash absorption spectroscopy study of the competition between ferredoxin and flavodoxin photoreduction by Photosystem I in Synechococcus sp. PCC 7002: Evidence for a strong preference for ferredoxin

  • Karen Meimberg
  • Ulrich Mühlenhoff

Abstract

The competition between ferredoxin and flavodoxin for electrons from Photosystem I was analyzed by flash absorption spectroscopy of the photoreduction processes that take place in the presence of both acceptor proteins in vitro. Steady state photoreduction assays indicate a strong inhibition of the apparent flavodoxin photoreduction activities of Photosystem I in the presence of ferredoxin. Flash-absorption experiments carried out at 626 nm, a wavelength where the reduction of ferredoxin shows no spectral contribution, show that the photoreduction of oxidized flavodoxin and flavodoxin semiquinone are inhibited by ferredoxin in a quantitatively similar way. The experimental data can be satisfactorily described by a reaction model that assumes that both redox states of flavodoxin do not compete with ferredoxin for binding on PS I and that the binding equilibrium between ferredoxin and PS I is not changed in their presence. In contrast, a model which assumes that ferredoxin and flavodoxin actually compete for binding to PS I gives poor results. Similarly, experimental data observed in the presence of both redox states of flavodoxin can also be quantitatively described under the assumption that the binding equilibrium between flavodoxin semiquinone and PS I is not disturbed by oxidized flavodoxin. Taken together, this analysis shows that PS I favors ferredoxin over flavodoxin and flavodoxin semiquinone over oxidized flavodoxin. This behavior is in accordance with the values of the dissociation constants for complexes between PS I and its acceptors. However, in case of ferredoxin the observed preference is stronger than expected from these values, indicating that ferredoxin is almost absolutely preferred by PS I over flavodoxin and is always reduced first.

cyanobacteria electron transfer flavoproteins iron–sulfur proteins Photosystem I soluble electron carriers 

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. Barth P, Lagoutte B and Setif P (1998) Ferredoxin reduction by Photosystem I from Synechocystis sp. PCC 6803: Toward an understanding of the respective roles of subunits PsaD and PsaE in ferredoxin binding. Biochemistry 37: 16233–16241PubMedGoogle Scholar
  2. Bianchi V, Eliasson R, Fontecave M, Mulliez E, Hoover DM, Matthews RG and Reichard P (1993) Flavodoxin is required for the activation of the anaerobic ribonucleotide reductase. Biochem Biophys Res Commun 197: 792–797PubMedGoogle Scholar
  3. Blaschkowski HP, Neuer G, Ludwig-Festl M and Knappe J (1982) Routes of flavodoxin and ferredoxin reduction in Escherichia coli. Eur J Biochem 123: 563–569PubMedGoogle Scholar
  4. Chitnis VP, Jung YS, Albee L, Golbeck JH and Chitnis PR (1996) Mutational analysis of Photosystem I polypeptides; role of PsaD and the lysyl 106 residue in the reductase activity of Photosystem I. J Biol Chem 271: 11772–11780PubMedGoogle Scholar
  5. Fischer N, Hippler M, Sétif P, Jacquot J-P and Rochaix J-D (1998) The PsaC subunit of Photosystem I provides an essential lysine residue for fast electron transfer to ferredoxin. EMBO J 17: 849–858PubMedGoogle Scholar
  6. Fitzgerald MP, Rogers LJ, Rao KK and Hall DO (1980) Efficiency of ferredoxins and flavodoxins as mediators in systems for hydrogen evolution. Biochem J 192: 665–672PubMedGoogle Scholar
  7. Fillat MF, Sandmann G and Gómez-Moreno C (1988) Flavodoxin from the nitrogen-fixing cyanobacteria Anabaena sp. PCC 7119. Arch Microbiol 150: 160–164Google Scholar
  8. Fillat MF, Borrais WE and Weisbeck PJ (1991) Isolation and overexpression in Escherichia coli of the flavodoxin gene for Anabaena PCC 7119. Biochem J 280: 187–192PubMedGoogle Scholar
  9. Fujii K, Galivan JH and Huennekens FM (1977) Activation of the methionine synthase: A further characterization of the flavoprotein system. Arch Biochem Biophys 178: 662–670PubMedGoogle Scholar
  10. Ghassemian M and Straus NA (1996) Fur regulates the expression of iron-stress genes in the cyanobacterium Synechococcus sp. strain PCC 7942. Microbiology 142: 1469–1476PubMedGoogle Scholar
  11. Hanley J, Sétif P, Bottin H and Lagoutte B (1996) Mutagenesis of Photosystem I in the region of the ferredoxin cross-linking site: modification of positively charged amino acids. Biochemistry 35: 8563–8571PubMedGoogle Scholar
  12. Hoover DM, Jarret JT, Sands RH, Dunham WR, Ludwig ML and Matthews RG (1997) Interaction of Escherichia coli cobalmin dependent methionine synthase and its physiological partner flavodoxin: Binding of flavodoxin leads to axial ligand dissociation from the cobalmin cofactor. Biochemistry 36: 127–138PubMedGoogle Scholar
  13. Ke B (1973) The primary electron acceptor of Photosystem I. Biochim Biophys Acta 301: 1–33PubMedGoogle Scholar
  14. Knaff DB (1996) Ferredoxin and ferredoxin-dependent chloroplast enzymes. In: Ort DR and Yocum CF (eds) Advances in Photosynthesis, Oxygenic Photosynthesis: The Light Reactions, pp 333–361. Kluwer Academic Publishers, Dordrecht, The NetherlandsGoogle Scholar
  15. Knaff DB and Hirasawa M (1991) Ferredoxin-dependent chloroplast enzymes. Biochim Biophys Acta 1056: 93–125PubMedGoogle Scholar
  16. Kruip J, Chitnis P, Lagoutte B, Rögner M and Boekema EJ (1997) Structural Organization of the major subunits in cyanobacterial Photosystem I; localization of subunits PsaC,-D,-E,-F and J. J Biol Chem 272: 17061–17069PubMedGoogle Scholar
  17. La Roche J, Boyd PW, McKay RML and Gelder RJ (1996) Flavodoxin as an in situ marker for iron stress in phytoplankton. Nature 382: 802–805Google Scholar
  18. Lelong C, Sétif P, Lagoutte B and Bottin H (1994) Identification of the amino acids involved in the functional interaction between Photosystem I and ferredoxin from Synechocystis sp. PCC 6803 by chemical cross-linking. J Biol Chem 269: 10034–10039PubMedGoogle Scholar
  19. Lelong C, Boekema E, Kruip J, Bottin H, R+gner M and Sétif P (1996) Characterization of a redox-active cross-linked complex between cyanobacterial Photosystem I and soluble ferredoxin. EMBO J 15: 2160–2168PubMedGoogle Scholar
  20. Leonhardt K and Straus NA (1992) An iron stress operon involved in the photosynthetic electron transport in the marine cyanobacterium Synechococcus sp. PCC 7002. J Gen Microbiol 138: 1613–1621PubMedGoogle Scholar
  21. Mathis P and Sétif P (1981) Near infra-red absorption spectra of the chlorophyll a cations and triplet states in vitro and in vivo. Isr J Chem 21: 316–320Google Scholar
  22. Matsubara H and Wada K (1988) Soluble cytochromes and ferredoxins. Methods Enzymol 167: 387–410PubMedGoogle Scholar
  23. Mayhew SG and Ludwig ML (1975) Flavodoxins and electron transferring flavoproteins. In: Boyer PD (ed) The Enzymes, Vol XII, pp 57–118. Academic Press, LondonGoogle Scholar
  24. Mayhew SG and Tollin G (1992) General properties of flavodoxins. In: Müller F (ed) Chemistry and Biochemistry of Flavoenzymes, Vol III, pp 389–426. CRC Press, Boca Raton, FLGoogle Scholar
  25. McKay RML, Geider RJ and LaRoche, J (1997) Physiological and biological response of the photosynthetic apparatus of two marine diatoms to Fe stress. Plant Physiol 114: 615–622PubMedGoogle Scholar
  26. Meimberg K, Lagoutte B, Bottin H and Mühlenhoff U (1998) The PsaE subunit is required for complex formation between Photosystem I and flavodoxin from the cyanobacterium Synechocystis sp. PCC 6803. Biochemistry 37: 9759–9767PubMedGoogle Scholar
  27. Meimberg K, Fischer N, Rochaix J-D and Mühlenhoff U (1999) Lysine 35 of PsaC is required for the efficient photoreduction of flavodoxin by Photosystem I from Chlamydomonas reinhardtii. Eur J Biochem 263: 137–144PubMedGoogle Scholar
  28. Morand LZ, Cheng RH, Krogman DW and Ki Ho K (1994) Soluble electron transfer catalysts of cyanobacteria. In: Bryant DA (ed) Advances in Photosynthesis, The Molecular Biology of Cyanobacteria, pp 381–407. Kluwer Academic Publishers, Dordrecht, The NetherlandsGoogle Scholar
  29. Mühlenhoff U and Sétif P (1996) Laser-flash absorption spectroscopy study of flavodoxin reduction by Photosystem I in Synechococcus sp. PCC 7002. Biochemistry 35: 1367–1374PubMedGoogle Scholar
  30. Mühlenhoff U, Kruip J, Bryant DA, Rögner M, Sétif P and Boekema E (1996a) Characterization of an redox-active cross-linked complex between cyanobacterial Photosystem I and its physiological acceptor flavodoxin. EMBO J 15: 484–497Google Scholar
  31. Mühlenhoff U, Zhao J and Bryant DA (1996b) Interaction between Photosystem I and flavodoxin from the cyanobacterium Synechococcus sp. PCC 7002 as revealed by chemical cross-linking. Eur J Biochem 235: 324–331PubMedGoogle Scholar
  32. Poncelet M, Cassier-Chauvat C, Leschelle X, Bottin H and Chauvat F (1998) Targeted deletion and mutational analysis of the essential (2Fe–2S) plant-like ferredoxin in Synechocystis PCC 6803 by plasmid shuffling. Mol Microbiol 28: 813–821PubMedGoogle Scholar
  33. Rogers LJ (1987) Ferredoxins, flavodoxins and related proteins: structure, function and evolution. In: Fay P and Van Baalen C (eds) The Cyanobacteria, pp 35–61. Elsevier, AmsterdamGoogle Scholar
  34. Rousseau F, Sétif P and Lagoutte B (1993) Evidence for the involvement of PS I-E subunit in the reduction of ferredoxin by Photosystem I. EMBO J 12: 1755–1765PubMedGoogle Scholar
  35. Sandmann G, Peleato ML, Fillat MF, Lazaro MC and Gömez-Moreno C (1990) Consequences of iron-dependent formation of ferredoxin and flavodoxin on photosynthesis and nitrogen fixation in Anabaena strains. Photosynth Res 26: 119–125Google Scholar
  36. Sétif PQY and Bottin H (1994) Laser-flash absorption spectroscopy study of ferredoxin reduction by Photosystem I in Synechocystis sp. PCC 6803: Evidence for submicrosecond and microsecond kinetics. Biochemistry 33: 8495–8504PubMedGoogle Scholar
  37. Sétif PQY and Bottin H (1995) Laser-flash absorption spectroscopy study of ferredoxin reduction by Photosystem I: Spectral and kinetic evidence for the existence of several Photosystem I – ferredoxin complexes. Biochemistry 34: 9059–9070PubMedGoogle Scholar
  38. Straus NA (1994) Iron Deprivation: physiology and gene regulation. In: Bryant DA (ed) Advances in Photosynthesis, The Molecular Biology of Cyanobacteria, pp 731-750. Kluwer Academic Publishers, Dordrecht, The NetherlandsGoogle Scholar
  39. Vigara AJ, Inda LA, Vega JM, Gómez-Moreno C and Peleato ML (1998) Flavodoxin as an electron donor in photosynthetic inorganic nitrogen assimilation by iron-deficient Chlorella fusca cells. Photochem and Photobiol 67: 446–449Google Scholar
  40. Vinnemeier J, Kunert A and Hagemann M (1998) Transcriptional analysis of the isiAB operon in salt-stressed cells of the cyanobacterium Synechocystis sp. PCC 6803. FEMS Microbiol Lett 169: 323–330PubMedGoogle Scholar
  41. Walker MC, Pueyo JJ, Gómez-Moreno C and Tollin G (1990) Comparison of the kinetics of reduction and intramolecular electron transfer in electrostatic and covalent complexes of ferredoxin–NADP+ reductase and flavodoxin from Anabaena PCC 7119. Arch Biochem Biophys 281: 76–83PubMedGoogle Scholar
  42. Zanetti G and Merati G (1987) Interaction between Photosystem I and ferredoxin, identification by chemical cross-linking of the polypeptide which binds ferredoxin. Eur J Biochem 169: 143–146PubMedGoogle Scholar
  43. Zhao JD, Li RG and Bryant DA (1998) Measurement of Photosystem I activity with photoreduction of recombinant flavodoxin. Anal Biochem 264: 263–270PubMedGoogle Scholar

Copyright information

© Kluwer Academic Publishers 1999

Authors and Affiliations

  • Karen Meimberg
  • Ulrich Mühlenhoff

There are no affiliations available

Personalised recommendations