1887

Abstract

The growth attributes of an aerobic nitrogen-fixing strain, Miami BG 043511, under aerobic and microaerobic/anaerobic conditions were examined using conventional batch and synchronous culture methods. Generation times of this strain, estimated from the increase in cell density under aerobic and anaerobic batch culture conditions, were 19-23 h and 15-19 h at 30 °C, respectively. It seems, therefore, that atmospheric oxygen did not seriously affect diazotrophic growth in this strain. Under a periodic light-dark regime, cells grew synchronously even under microaerobic/anaerobic conditions. When the aerobic culture entered the light period, a peak of photosynthetic activity was followed by a peak of nitrogenase activity. In contrast, a peak of nitrogenase activity preceded a peak of photosynthetic activity under microaerobic/anaerobic conditions. In both cases, however, cell division was observed at or just after the peak of photosynthetic activity. The difference in the timing of the appearance of nitrogenase activity in microaerobic/anaerobic cultures was ascribed to the inability of cells to generate sufficient ATP under anaerobic dark conditions. Periodic changes in cellular carbohydrate content, associated with the periodic appearances of photosynthetic and nitrogen-fixing activities, were observed under both aerobic and microaerobic/anaerobic conditions. Cellular carbohydrate content increased from 10% to 60% of cell dry weight during the phase of photosynthesis under aerobic conditions, while it reached only 40% under microaerobic/anaerobic conditions. The amount of reserve polysaccharides required to support nitrogen fixation was larger in aerobic cultures than in microaerobic/anaerobic cultures.

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1994-08-01
2024-12-03
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References

  1. Dubois M., Gilies K.A., Hamilton K., Rebers P.A., Smith F. Colorimetric method for determination of sugars and related substances. Anal Chem 1956; 28:350–356
    [Google Scholar]
  2. Fay P. Oxygen relations of nitrogen fixation in cyanobacteria. Microbiol Rev 1992; 56:340–373
    [Google Scholar]
  3. Gallon J.R. Reconciling the incompatible: N2 fixation and 02. New Phytol 1992; 122:571–609
    [Google Scholar]
  4. Kumazawa S., Mitsui A. Comparative study of uptake hydrogenase and hydrogen photoproduction activities between heterocystous cyanobacterium Anabaena cylindrica B629 and non-heterocystous cyanobacterium Oscillatoria sp strain Miami BG 7. Appl Environ Microbiol 1985; 50:287–291
    [Google Scholar]
  5. Kumazawa S., Mitsui A. Photosynthetic activities of a synchronously grown aerobic N2-fixing unicellular cyanobacterium, Synechococcus sp Miami BG 043511. J Gen Microbiol 1992; 138:467–472
    [Google Scholar]
  6. Leon C., Kumazawa S., Mitsui A. Cyclic appearance of aerobic nitrogenase activity during synchronous growth of unicellular cyanobacteria. Curr Microbiol 1986; 13:149–153
    [Google Scholar]
  7. Maryan P.S., Eady R.R., Chaplin A.E., Gallon J.R. Nitrogen fixation by Gloeothece sp. PCC 6909: respiration and not photosynthesis supports nitrogenase activity in the light. J Gen Microbiol 1986; 132:789–796
    [Google Scholar]
  8. Mitsui A., Cao S. Isolation and culture of marine nitrogen-fixing unicellular cyanobacteria Synechococcus. Methods Enzymol 1988; 167:105–113
    [Google Scholar]
  9. Mitsui A., Phlips E.J., Kumazawa S., Reddy K.J., Ramachandran S., Matsunaga T., Haynes L., Ikemoto H. Progress in research toward outdoor biological hydrogen production using solar energy, sea water, and marine photosynthetic microorganisms. Ann NY Acad Sci 1983; 413:514–530
    [Google Scholar]
  10. Mitsui A., Kumazawa S., Takahashi A., Ikemoto H., Cao S., Arai T. Strategy by which nitrogen-fixing unicellular cyanobacteria grow photoautotrophically. Nature 1986; 323:720–722
    [Google Scholar]
  11. Mitsui A., Cao S., Takahashi A., Arai T. Growth synchrony and cellular parameters of the unicellular nitrogen-fixing marine cyanobacterium, Synechococcus sp strain Miami BG 043511 under continuous illumination. Physiol Plant 1987; 69:1–8
    [Google Scholar]
  12. Mitsui A., Suda S., Hanagata N. Cell cycle events at different temperatures in aerobic nitrogen-fixing marine unicellular cyanobacterium Synechococcus sp Miami BG 043511. J Mar Biotechnol 1993; 1:89–91
    [Google Scholar]
  13. Ortega-Calvo J.-J., Stal L.J. Diazotrophic growth of the unicellular cyanobacterium Gloeothece sp PCC 6909 in continuous culture. J Gen Microbiol 1991; 137:1789–1797
    [Google Scholar]
  14. Spiller H., Shanmugam K.T. Physiological conditions for nitrogen fixation in a unicellular marine cyanobacterium, Synechococcus sp strain SF1. J Bacteriol 1987; 169:5379–5384
    [Google Scholar]
  15. Suda S., Kumazawa S., Mitsui A. Change in the H2 photoproducing capability in a synchronously grown aerobic nitrogen-fixing cyanobacterium, Synechococcus sp Miami BG 043511. Arch Microbiol 1992; 158:1–4
    [Google Scholar]
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