1887

Abstract

Summary: [C]Methylamine uptake by free-living sp. ANU289 had Michaelis–Menten kinetics (apparent 6.6 μm). Uptake was competitively inhibited by ammonia ( 0.4 μm) and was dependent on an energized membrane. Uptake by bacteria had an optimum at pH 7.0. Methylamine uptake by bacteroids from siratro root nodules was much slower than that by free-living bacteria at pH 7.0 but increased exponentially with the pH of the medium. Uptake by bacteroids did not show saturation kinetics and was insensitive to the presence of ammonia or uncouplers. These results suggest that free-living bacteria (grown under conditions where ammonia is limiting) have an active transport mechanism for the uptake of ammonium ions; this carrier is not operative in the symbiotic state, where passive diffusion of ammonia occurs. In the free-living state, the ammonium carrier is under genetic control, being repressed by growth on high concentrations of ammonia. Derepression occurs under conditions of nitrogen starvation.

Loading

Article metrics loading...

/content/journal/micro/10.1099/00221287-132-2-257
1986-02-01
2024-12-09
Loading full text...

Full text loading...

/deliver/fulltext/micro/132/2/mic-132-2-257.html?itemId=/content/journal/micro/10.1099/00221287-132-2-257&mimeType=html&fmt=ahah

References

  1. Bergersen F. J., Turner G. L. 1978; Activity of nitrogenase and glutamine synthetase in relation to availability of oxygen in continuous cultures of cowpea Rhizobium sp. supplied with excess ammonium. Biochimica et biophysica acta 538:406–416
    [Google Scholar]
  2. Dilworth M. J., Glenn A. R. 1982; Movements of ammonia in Rhizobium leguminosarum. Journal of General Microbiology 128:29–37
    [Google Scholar]
  3. Glenn A. R., Dilworth M. J. 1984; Methylamine and ammonium transport systems in Rhizobium leguminosarum MNF3841. Journal of General Microbiology 130:1961–1968
    [Google Scholar]
  4. Gober J. W., Kashket E. R. 1983; Methylammonium uptake by Rhizobium sp. 32H1. Journal of Bacteriology 153:1196–1201
    [Google Scholar]
  5. Howitt S. M., Gresshoff P. M. 1985; Ammonia regulation of glutamine synthetase in Rhizobium sp. ANU289. Journal of General Microbiology 131:1433–1440
    [Google Scholar]
  6. Jayakumar A., Barnes E. M. 1984; The role of glutamine in regulation of ammonium transport in Azotobacter vinelandii. Archives of Biochemistry and Biophysics 231:95–101
    [Google Scholar]
  7. Kleiner D. 1981; The transport of NH3 and NH+ 4 across biological membranes. Biochimica et biophy-sica acta 639:41–52
    [Google Scholar]
  8. Kleiner D. 1982; Ammonium (methylammonium) transport by Klebsiella pneumoniae. Biochimica et biophysica acta 688:702–708
    [Google Scholar]
  9. Kleiner D., Fitzke E. 1981; Some properties of a new electrogenic transport system: the ammonium (methylammonium) carrier from Clostridium pas-teurianum. Biochimica et biophysica acta 641:138–147
    [Google Scholar]
  10. Laane C., Krone W., Konings W., Veeger C. 1980; Short term effect of ammonium chloride on nitrogen fixation by Azotobacter vinelandii and by bacteroids of Rhizobium leguminosarum. European Journal of Biochemistry 103:39–46
    [Google Scholar]
  11. Marsh S. D., Wyza R. E., Evans W. R. 1984; Uptake of ammonia and methylamine by free-living and symbiotic Rhizobium. Plant Physiology 75S, abst.:155–p. 28.
    [Google Scholar]
  12. Mohapatra S. S., Bender G. L., Shine J., Rolfe B. G., Gresshoff P. M. 1983; In vitro expression of nitrogenase activity in Parasponia Rhizobium strain ANU289. Archives of Microbiology 134:12–16
    [Google Scholar]
  13. O´Gara F., Shanmugam K. T. 1976; Regulation of nitrogen fixation by rhizobia. Biochimica et biophysica acta 437:313–321
    [Google Scholar]
  14. O´Hara G. W., Riley I. T., Glenn A. R., Dilworth M. J. 1985; The ammonium permease of Rhizobium leguminosarum MN3841. Journal of General Microbiology 131:757–764
    [Google Scholar]
  15. Rai A. N., Rowell P., Stewart W. D. P. 1984; Evidence for an ammonium transport system in free-living and symbiotic cyanobacteria. Archives of Microbiology 137:241–246
    [Google Scholar]
  16. Sandeman R. A., Gresshoff P. M. 1985; Nitrogenase activity and inactivation in isolated bacteroids from the legume siratro and the nonlegume Parasponia rigida. Plant Science Letters 37:199–204
    [Google Scholar]
  17. Schacterle G. R., Pollack R. L. 1973; Simplified method for quantitative assay of small amounts of protein in biological material. Analytical Biochemistry 51:654–655
    [Google Scholar]
  18. Tubb R. S. 1976; Regulation of nitrogen fixation in Rhizobium spp. Applied and Environmental Microbiology 32:483–488
    [Google Scholar]
/content/journal/micro/10.1099/00221287-132-2-257
Loading
/content/journal/micro/10.1099/00221287-132-2-257
Loading

Data & Media loading...

This is a required field
Please enter a valid email address
Approval was a Success
Invalid data
An Error Occurred
Approval was partially successful, following selected items could not be processed due to error