Photosynthetica 1999, 36(3):389-395 | DOI: 10.1023/A:1007071902295

Role of Nitrate in Photosynthetic Electron Transport of Chlorella Vulgaris

M. El-Anwar H. Osman, A.H. El-Naggar

Addition of nitrate to a suspension of NO3 --depleted Chlorella vulgaris cells raised the O2-evolving capacity of the organism by 60%. The rate of O2-evolution under flash irradiation of the depleted cells was drastically reduced, which could be restored by addition of NO3 -. The 2,5-dibromo-3-methyl-6-isopropyl-p-benzoquinone (DBMIB)-insensitive O2-evolution, i.e., photosystem (PS) 2 activity of NO3--depleted cells, showed a 75% stimulation by addition of NO3 -. PS1-mediated electron transport was also stimulated (50%) by addition of NO3 -. Fluorescence yields of the NO3 --depleted cells were significantly reduced. A normal fluorescence response was restored by the addition of NO3 -. The fluorescence yield of the NO3 --depleted and DCMU-treated-cells increased significantly after addition of NO3 - ions, indicating a further reduction of the primary acceptor of PS2 (Q). In addition, the low temperature fluorescence emission spectra showed that energy transfer to PS2 and PS1 was much higher when nitrate was present. Hence nitrate accelerates the light-induced charge transfer from the intact O2-evolving system to the primary electron acceptor of PS2 and stimulates the PS1-mediated electron transport.

Additional key words: chlorophyll fluorescence; DCMU; 2,5-dibromo-3-methyl-6-isopropyl-p-benzoquinone; oxygen evolution rate; photosystem 1 and 2 activities

Published: August 1, 1999  Show citation

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El-Anwar Osman, M.H., & El-Naggar, A.H. (1999). Role of Nitrate in Photosynthetic Electron Transport of Chlorella Vulgaris. Photosynthetica, 36(3), 389-395. doi: 10.1023/A:1007071902295
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    References

    1. Allen, F.E, Grimshaw, H.M, Parainson, J.A, Quarmby, C.: Chemical Analysis of Ecological Material.-Blackwell, London 1974.
    2. Butler, W.L.: Fluorescence yield in photosynthetic systems and its relation to electron transport.-In: Sanadi, D.R. (ed.): Current Topics in Bioenergetics. Vol. 1. Pp. 49-73. Acad. Press, New York 1966. Go to original source...
    3. Cho, F., Spencer, J., Govindjee: Emission spectra of Chlorella at very low temperature (-296° to -196°).-Biochim. biophys. Acta 126: 174-176, 1966. Go to original source...
    4. De la Torre, A., Delgado, B., Lara, C.: Nitrate dependent O2 evolution in intact leaves.-Plant Physiol. 96: 898-901, 1991. Go to original source...
    5. Duysens, L.N.M., Sweers, H.E.: Mechanism of two photochemical reactions in algae by means of fluorescence.-In: Studies on Microalgae and Photosynthetic Bacteria. Pp. 353-372. University of Tokyo Press, Tokyo 1963.
    6. Harnischfeger, G.: The use of fluorescence emission at 77 °K in the analysis of the photosynthetic apparatus of higher plants and algae.-Adv. bot. Res. 5: 1-52, 1977. Go to original source...
    7. Joliot, P., Joliot, A.: A polarographic method for detection of oxgen production and reduction of Hill reagent by isolated chloroplasts.-Biochim. biophys. Acta 153: 625-634, 1968. Go to original source...
    8. Kelley, P.M., Izawa, S.: The role of chloride ion in photosystem II. I. Effects of chloride ion on photosystem II electron transport and on hydroxylamine inhibition.-Biochim. biophys. Acta 502: 198-210, 1978. Go to original source...
    9. Lorenzen, H.: Synchronization of Chlorella with light-dark changes and periodical dilution to a standard cell number.-In: Zeiten, E. (ed.): Synchrony of Cell Division and Growth. Pp. 571. Interscience, New York 1964.
    10. Losada, M., Guerrero, M.G.: The photosynthetic reduction of nitrate and its regulation.-In: Barber, J. (ed.): Photosynthesis in Relation to Model Systems. Pp. 365-408. Elsevier, Amsterdam-New York-Oxford 1979.
    11. Marek, M., Beranová, J.: [Effect of increasing concentrations of nitrates in nutrient medium on the photosynthetic characteristics of primary leaves of spring barley (Hordeum vulgare L.).]-Rostlinná Výroba (Praha) 35: 85-93, 1989. [In Czech.]
    12. Mende, D., Wiessner, W.: Bicarbonate in vivo requirement of photosystem II in the green alga Chlamydobotrys stellata.-J. Plant Physiol. 118: 259-266, 1985. Go to original source...
    13. Metzner, H., Rau, H., Senger, H.: Untersuchungen zur Synchronisierbarkeit einzelner Pigmentmangelmutanten von Chlorella.-Planta 65: 186-194, 1965. Go to original source...
    14. Osman, M.E.H., Metzner, H., Fisher, K.: Effects of nitrate on thylakoid reactions I. Influence on photosynthetic electron transport.-Photosynthetica 16: 7-12, 1982.
    15. Sayed, O.H.: Analysis of photosynthetic responses and adaptation to nitrogen starvation in Chlorella using in vivo chlorophyll fluorescence.-Photosynthetica 35: 611-619, 1998. Go to original source...
    16. Stemler, A.: The functional role of bicarbonate in photosynthetic light reaction II.-In: Govindjee (ed.): Photosynthesis. Vol. II. Pp. 513-539. Acad. Press, New York-London-Paris-San Diego-San Francisco-São Paulo-Sydney-Tokyo-Toronto 1982. Go to original source...
    17. Warburg, O., Krippahl, G., Jetschmann, C.: Widerlegung der Photolyse des Wassers und Beweis der Photolyse der Kohlensäure nach Versuchen mit lebender Chlorella und den Hill-Reagentien Nitrat und K3Fe(CN)6.-Z. Naturforsch. 20b: 993-996, 1965. Go to original source...
    18. Warburg, O., Negelein, E.: Über die Reduktion der Salpetersäure in grünen Zellen.-Biochem. Z. 110: 66-115, 1920. Go to original source...
    19. Wiessner, W., Dubertret, G., Henry-Hiss, Y., Mende, D., Lefort-Tran, M.: Fluorescence transients as indicator for the existence of regulatory mechanisms in photosynthetic electron transport.-Ber. deutsch. bot. Ges. 94: 503-515, 1981. Go to original source...

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