Oxygen sensitivity of algal H2- production

  • Maria L. Ghirardi
  • Robert K. Togasaki
  • Michael Seibert
Session 2 Biological Research


Photoproduction of H2 by green algae utilizes electrons originating from the photosynthetic oxidation of water and does not require metabolic intermediates. However, algal hydrogenases are extremely sensitive to O2, which limits their usefulness in future commercial H2-production systems. We designed an experimental technique for the selection of O2-tolerant, H2-producing variants ofChlamydomonas reinhardtii based on the ability of wild-type cells to survive a short (20 min) exposure to metronidazole in the presence of controlled concentrations of O2. The number of survivors depends on the metronidazole concentration, light intensity, preinduction of the hydrogenase, and the presence or absence of O2. Finally, we demonstrate that some of the selected survivors in fact exhibit H2-production capacity that is less sensitive to O2 than the original wild-type population.

Index Entries

Hydrogen green algae Chlamydomonas oxygen metronidazole 



adenosine triphosphate


cell wall-less strain ofChlamydomonas reinhardtii






inhibitor concentration that decreases the rate of an enzymatic reaction to 50% of the rate measured in the absence of the inhibitor

MNZ metronidazole



nicotinamide adenine dinucleotide phosphate


reduced form of NADP


initial rate of an enzymatic reaction




  1. 1.
    Weaver, P. F., Lien, S., and Seibert, M. (1979), inProceedings of the Fifth ]oint US/USSR Conference of the Microbial Enzyme Reactions Project, Jurmala, Latvia, USSR, pp. 461–479.Google Scholar
  2. 2.
    Benneman, J. R. (1994), inProceedings of the 10th World Hydrogen Energy Conference, Cocoa Beach, FL.Google Scholar
  3. 3.
    Greenbaum, E., Lee, J. W., Tevault, C. V., Blankinship, S. L., and Mets, L. J. (1995),Nature 376, 438–441.CrossRefGoogle Scholar
  4. 4.
    Weaver, P. F., Lien, S., and Seibert, M. (1980),Solar Energy 24, 3–45.CrossRefGoogle Scholar
  5. 5.
    McBride, A. C., Lien, S., Togasaki, R. K., and San Pietro, A. (1977), inBiological Solar Energy Conversion, Mitsui, A., Miyachi, S., SanPietro, A., and Tamura, S. eds. Academic Press, New York, NY.Google Scholar
  6. 6.
    Harris, E. H. (1989),The Chlamydomonas Sourcebook, Academic Press, New York.Google Scholar
  7. 7.
    Vladimirova, M. G. and Markelova, A. G. (1980),Sov. Plant Physiol. 27, 878–889.Google Scholar
  8. 8.
    Happe, T., Mosler, B., and Naber, J. D. (1994),Eur. J. Biochem. 222, 769–774.CrossRefGoogle Scholar
  9. 9.
    Roessler, P. and Lien, S. (1982),Arch. Biochem. Bwphys. 213, 37–44.CrossRefGoogle Scholar
  10. 10.
    McTavish, H., Picorel, R., and Seibert, M. (1989),Plant Physiol. 89, 452–456.CrossRefGoogle Scholar
  11. 11.
    Roessler, P. G. and Lien, S. (1984),Plant Physiol. 76, 1086–1089.Google Scholar
  12. 12.
    Asada, K. (1984),Methods in Enzymology vol.105, Academic Press, New York, NY, pp. 422–29.Google Scholar
  13. 13.
    Schmidt, G. W., Matlin, K. S., and Chua, N.-H. (1977),Proc. Natl. Acad. Sci. USA 74, 610–614.CrossRefGoogle Scholar
  14. 14.
    Church, D. L. and Laishley, E. J. (1995),Anaerobe 1, 81–92.CrossRefGoogle Scholar
  15. 15.
    Wardman, P. and Clarke, E. D. (1976),Biochem. Biophys. Res. Comm. 69, 942–949.CrossRefGoogle Scholar
  16. 16.
    Fridovich, I. (1974), inAdvances in Enzymology, vol.41, Meister, A., ed., Wiley Interscience, New York, NY, pp. 35–97.Google Scholar
  17. 17.
    Kindle, K. L. (1990),Proc Natl Acad Sci USA 87, 1228–1232.CrossRefGoogle Scholar

Copyright information

© Humana Press Inc. 1997

Authors and Affiliations

  • Maria L. Ghirardi
    • 1
  • Robert K. Togasaki
    • 2
  • Michael Seibert
    • 1
  1. 1.Notional Renewable Energy LaboratoryGolden
  2. 2.Department of BiologyIndiana UniversityBloomington

Personalised recommendations