Photosynthesis Research

, Volume 65, Issue 3, pp 261–268 | Cite as

Kinetics of absorbance and anisotropy upon excited state relaxation in the reaction center core complex of a green sulfur bacterium

  • Sieglinde Neerken
  • Ying-Zhong Ma
  • Jochen Aschenbrücker
  • Kristiane A. Schmidt
  • Frank R. Nowak
  • Hjalmar P. Permentier
  • Thijs J. Aartsma
  • Tomas Gillbro
  • Jan Amesz
Article

Abstract

Properties of the excited states in reaction center core (RCC) complexes of the green sulfur bacterium Prosthecochloris aestuarii were studied by means of femtosecond time-resolved isotropic and anisotropic absorption difference spectroscopy at 275 K. Selective excitation of the different transitions of the complex resulted in the rapid establishment of a thermal equilibrium. At about 1 ps after excitation, the energy was located at the lowest energy transition, BChl a 835. Time constants varying between 0.26 and 0.46 ps were observed for the energy transfer steps leading to this equilibrium. These transfer steps were also reflected in changes in polarization. Our measurements indicate that downhill energy transfer towards excited BChl a 835 occurs via the energetically higher spectral forms BChl a 809 and BChl a 820. Low values of the anisotropy of about 0.07 were found in the ‘two-color’ measurements at 820 and 835 nm upon excitation at 800 nm, whereas the ‘one-color’ kinetics showed much higher anisotropies. Charge separation occurred with a time constant varying between 20 and 30 ps.

anisotropy bacteriochlorophyll a excited states green sulfur bacteria reaction center 

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. Albrecht AC (1961) Polarizations and assignments of transitions: The method of photoselection. J Mol Spectr 6: 84–108CrossRefGoogle Scholar
  2. Cong P, Deuel HP and Simon J (1993) Using optical coherence to measure the ultrafast electronic dephasing of large molecules in room-temperature liquid. Chem Phys Lett 212: 367–373CrossRefGoogle Scholar
  3. Feiler U and Hauska G (1995) The reaction center from green sulfur bacteria. In: Blankenship RE, Madigan MT and Bauer CE (eds) Anoxygenic Photosynthetic Bacteria, pp 665–685. Kluwer Academic Publishers, Dordrecht, The NetherlandsGoogle Scholar
  4. Francke C, Permentier HP, Franken EM, Neerken S and Amesz J (1997) Isolation and properties of photochemically active reaction center complexes from the green sulfur bacterium Prosthecochloris aestuarii. Biochemistry 36: 14167–14172PubMedCrossRefGoogle Scholar
  5. Franken EM, Neerken S, Louwe RJW, Amesz J and Aartsma TJ (1998) A permanent holeburning study of the FMO antenna complex. Biochemistry 37: 5046–5051PubMedCrossRefGoogle Scholar
  6. Kennis JTM (1997) Exciton coupling, energy transfer and photochemical conversion in purple photosynthetic bacteria. PhD Thesis, Leiden UniversityGoogle Scholar
  7. Kirmaier C and Holten D (1990) Evidence that a distribution of bacterial reaction centers underlies the temperature and detection-wavelength dependence of the rates of the primary electron-transfer reactions. Proc Natl Acad Sci USA 87: 3552–3556PubMedCrossRefGoogle Scholar
  8. Kobayashi M, Oh-oka H, Akutsu S, Akiyama M, Tominaga K, Kise H, Nishida F, Watanabe T, Amesz J, Koizumi M, Ishida N and Kano H (2000) The primary electron acceptor of green sulfur bacteria, bacteriochlorophyll 663, is a chlorophyll a esterified with Δ 2,6-phytadienol. Photosynthe Res 63: 269–280CrossRefGoogle Scholar
  9. Knox RS and Gülen D (1993) Theory of polarized fluorescence from molecular pairs: Förster transfer at large electronic coupling. Photochem Photobiol 57: 40–43Google Scholar
  10. Ma Y-Z, Aschenbrücker J, Miller M and Gillbro T (1999) Ground-state vibrational coherence in chlorosomes of the green sulfur photosynthetic bacterium Chlorobium phaeobacteroides. Chem Phys Lett 300: 465–472CrossRefGoogle Scholar
  11. Müller MG, Griebenow K and Holzwarth AR (1992) Primary processes in isolated bacterial reaction centers from Rhodobacter sphaeroides studied by picosecond fluorescence kinetics. Chem Phys Lett 199: 465–469CrossRefGoogle Scholar
  12. Neerken S, Permentier HP, Francke C, Aartsma TJ and Amesz J (1998) Excited states and trapping in reaction center complexes of the green sulfur bacterium Prosthecochloris aestuarii. Biochemistry 37: 10792–10797PubMedCrossRefGoogle Scholar
  13. Neerken S, Schmidt KA, Aartsma TJ and Amesz J (1999) Dynamics of energy conversion in reaction center core complexes of the green sulfur bacterium Prosthecochloris aestuarii at low temperature. Biochemistry 38: 13216–13222PubMedCrossRefGoogle Scholar
  14. Neerken S, Aartsma TJ and Amesz J (2000) Pathways of energy transformation in antenna reaction center complexes of Heliobacillus mobilis. Biochemistry 39: 3297–3303PubMedCrossRefGoogle Scholar
  15. Nuijs AM, Vasmel H, Joppe HLP, Duysens LNM and Amesz J (1985) Excited states and primary charge separation in the pigment system of the green photosynthetic bacterium Prosthecochloris aestuarii as studied by picosecond absorbance difference spectroscopy. Biochim Biophys Acta 807: 24–34CrossRefGoogle Scholar
  16. Permentier HP, Schmidt KA, Kobayashi M, Akiyama M, Hager-Braun C, Neerken S, Miller M and Amesz J (2000) Composition and optical properties of reaction centre core complexes from the green sulfur bacteria Prosthecochloris aestuarii and Chlorobium tepidum. Photosynth Res 64: 27–39PubMedCrossRefGoogle Scholar
  17. Schmidt KA, Neerken S, Permentier HP, Hager-Braun C and Amesz J (2000) Electron transfer in reaction center core complexes from the green sulfur bacteria Prosthecochloris aestuarii and Chlorobium tepidum. Biochemistry 39: 7212–7220PubMedCrossRefGoogle Scholar
  18. Wendling M, Pullerits T, Przyjalgowski MA, Vulto SIE, Aartsma TJ, Van Grondelle R and Van Amerongen H (2000) Electronvibrational coupling in the Fenna-Matthews-Olson complex of Prosthecochloris aestuarii determined by temperature dependent absorption and fluorescence line narrowing measurements. J Phys Chem B104: 5825–5831Google Scholar
  19. Wynne K and Hochstrasser RM (1993) Coherence effects in the anisotropy of optical experiments. Chem Phys 171: 179–188CrossRefGoogle Scholar

Copyright information

© Kluwer Academic Publishers 2000

Authors and Affiliations

  • Sieglinde Neerken
    • 1
  • Ying-Zhong Ma
    • 2
  • Jochen Aschenbrücker
    • 2
  • Kristiane A. Schmidt
    • 1
  • Frank R. Nowak
    • 1
  • Hjalmar P. Permentier
    • 1
  • Thijs J. Aartsma
    • 1
  • Tomas Gillbro
    • 2
  • Jan Amesz
    • 3
  1. 1.Department of Biophysics, Huygens LaboratoryLeiden UniversityLeidenThe Netherlands
  2. 2.Department of Physical ChemistryUmeå UniversityUmeåSweden
  3. 3.Department of Biophysics, Huygens LaboratoryLeiden UniversityLeidenThe Netherlands

Personalised recommendations