Gels pp 19-25 | Cite as

Photochemical activity of the bacterial reaction center in polymer-like phospholipids reverse micelles

  • G. Palazzo
  • M. Giustini
  • A. Mallardi
  • G. Colafemmina
  • M. Della Monica
  • A. Ceglie
Conference paper
Part of the Progress in Colloid & Polymer Science book series (PROGCOLLOID, volume 102)


An integral membrane protein, the photosynthetic bacterial reaction center (RC), has been incorporated in reverse micelle viscoelastic gels made of phosphatidylcholine and phosphatidylserine. Due to the dynamic nature of the gels, the use of a technique which shares the same timescale of the charge recombination is advised, in order to correlate the kinetic behaviour of the RC to the hosting-system properties. Self-diffusion and conductivity measurements have been used to investigate the properties of the model system lecithin/cyclohexane/water. The results indicate that such techniques can describe the properties of the system on a long characteristic time-scale. As a consequence, the kinetic behaviour of the RC has been studied by means of flash-spectro-photometry and related to the structural properties of the hosting gel, investigated by means of conductivity. The conductivity data are consistent with a water-induced sphere-to-rod transition of the phospholipid aggregates. Furthermore, increasing the ratio [water]/[lipid], a maximum in the hydrodynamic dimension of the giant worm-like reverse micelles is found. The experimental P+ decay has been resolved into three exponential components which are strongly affected by the system composition. The functionality of the binding site QB is dependent on the ratio [water]/[lipid] supporting the hypothesis of a water role in the binding process.

Key words

Charge-recombination organogels self-diffusion membrane model 


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  1. 1.
    Scartazzini R, Luisi PL (1988) J Phys Chem 92:829–833CrossRefGoogle Scholar
  2. 2.
    Schurtenberger P (1994) Chimia 48:72–78 and references thereinGoogle Scholar
  3. 3.
    Schurtenberger P, Cavaco C (1994) J Phys Chem 98:5481–5486CrossRefGoogle Scholar
  4. 4.
    Schurtenberger P, Cavaco C (1994) Langmuir 10:100–108CrossRefGoogle Scholar
  5. 5.
    Hong-Li W, Luisi PL (1991) Biochem Biophys Res Comm 177:897–900CrossRefGoogle Scholar
  6. 6.
    Ermler U, Fritzsch G, Buchanan W, Michel H (1994) Structure 2:925–936CrossRefGoogle Scholar
  7. 7.
    Feher G, Allen JP, Okamura MY, Rees DC (1989) 339:111–116Google Scholar
  8. 8.
    Shinkarev VP, Wraight CA (1993) In: Deisenhofer J, Norris JR (eds) The Photosynthetic Reaction Center. Academic Press, New York, pp 193–255Google Scholar
  9. 9.
    Agostiano A, Catucci L, Della Monica M, Mallardi A, Palazzo G, Venturoli G (1995) Bielectrochem Bioenerg 38:25–33CrossRefGoogle Scholar
  10. 10.
    Agostiano A, Catucci L,Colafemmina G, Della Monica M, Palazzo G, Giustini M, Mallardi A (1995) Gazz Chim Ital 125:615–622Google Scholar
  11. 11.
    Gray KA, Farchaus JW, Wachtveitl J, Breton J, Oesterhelt D (1990) EMBO J 9:2061–2070.Google Scholar
  12. 12.
    Giustini M, Palazzo G, Colafemmina G, Della Monica M, Giomini M, Ceglie A (1996) J Phys Chem 100:3190–3198CrossRefGoogle Scholar
  13. 13.
    Luisi PL, Scartazzini R, Haering G, Schurtenberger P (1990) Colloid Polym Sci 268:356–374CrossRefGoogle Scholar
  14. 14.
    Schurtenberger P, Scartazzini R, Luisi PL (1989) Rheologica Acta 28:372–381CrossRefGoogle Scholar
  15. 15.
    Cukier RI (1984) Macromolecules 17:252–255CrossRefGoogle Scholar
  16. 16.
    Eicke HF, Borkovec M, Bas-Gupta B (1989) J Phys Chem 93:314–318CrossRefGoogle Scholar
  17. 17.
    Callay N, Chittofrati A (1990) J Phys Chem 94:4755–4756CrossRefGoogle Scholar
  18. 18.
    boicelli CA, Giomini M, Giuliani AM (1981) Spectrochim Acta 37A:559–561Google Scholar
  19. 19.
    Boicelli CA, Conti F, Giomini M, Giuliani AM (1983) Gazz Chim Ital 113:573–577Google Scholar
  20. 20.
    Capitani D, Segre AL, Sparapani R, Giustini M, Scartazzini R, Luisi PL (1991) Langmuir 7:250–253CrossRefGoogle Scholar
  21. 21.
    Capitani D, Rossi E, Segre AL, Giustini M, Luisi PL (1993) Langmuri 9:685–689CrossRefGoogle Scholar
  22. 22.
    Weissenberg K (1974) Nature 159:310–313Google Scholar
  23. 23.
    Warncke K, Dutton PL (1993) Proc Natl Acad Sci USA 90:2920–2924CrossRefGoogle Scholar
  24. 24.
    Clayton RK (1978) Biochim Biophys Acta 504:255–264CrossRefGoogle Scholar
  25. 25.
    Mallardi A, Angelico R, Della Monica M, Giustini M, Palazzo G, Venturoli G (1995) In: Mathis P (ed) Photosynthesis: from light to biosphere. KLuwer AP, Amsterdam, Vol I: pp 843–846Google Scholar
  26. 26.
    Larson GW, Wraight CA (1995) Photosynth Res Supplement 1:65Google Scholar

Copyright information

© Dr. Dietrich Steinkopff Verlag GmbH & Co. KG 1996

Authors and Affiliations

  • G. Palazzo
    • 1
  • M. Giustini
    • 2
  • A. Mallardi
    • 2
  • G. Colafemmina
    • 1
  • M. Della Monica
    • 1
  • A. Ceglie
    • 3
  1. 1.Dipartimento di ChimicaUniversità di BariBariItaly
  2. 2.CNR C. Studi Chimico-Flsici sull’Interazione Luce-MateriaBariItaly
  3. 3.Facoltá di AgrariaUniversità del MoliseCampobassoItaly

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