1887

Abstract

Glutamate synthase, an enzyme involved in glutamate biosynthesis in nitrogen-deficient environments, has been purified 200-fold from the photosynthetic bacterium The association of this NADPH-linked glutamate synthase with the photosynthetic membranes was suggested by its co-sedimentation with the chromatophore membranes and its ability to couple glutamate formation to light-generated reducing power. Although it was not homogeneous, the enzyme co-chromatographed with iron after three successive column chromatography steps and had the spectrum of a flavoprotein which suggests it may be an iron-sulphur flavoprotein similar to the enzyme from other prokaryotes. The K values of glutamate synthase for NADPH, glutamine and 2-oxoglutarate were 15 µ, 130 µ and 35 µ, respectively. The molecular weight of glutamate synthase was salt-dependent in that the enzyme isolated in 0·4 -NaCl showed a molecular weight of 840000, whereas in the absence of salt the molecular weight was about 260000. This phenomenon may be common to other glutamate synthases, since the molecular weight of this enzyme from was also influenced in a similar manner by NaCl.

Loading

Article metrics loading...

/content/journal/micro/10.1099/00221287-123-2-335
1981-04-01
2022-01-22
Loading full text...

Full text loading...

/deliver/fulltext/micro/123/2/mic-123-2-335.html?itemId=/content/journal/micro/10.1099/00221287-123-2-335&mimeType=html&fmt=ahah

References

  1. Adachi K., Susuki I. 1977; Purification and properties of glutamate synthase from Thiobacillus thioparus . Journal of Bacteriology 129:1173–1182
    [Google Scholar]
  2. Andrews P. 1965; The gel-filtration behaviour of proteins related to their molecular weights over a wide range. Biochemical Journal 96:595–606
    [Google Scholar]
  3. Bender R. A., Janssen K. A., Resnick A. D., Blumenberg M., Foor F., Magasanik B. 1977; Biochemical parameters of glutamine synthetase from Klebsiella aerogenes . Journal of Bacteriology 129:1001–1009
    [Google Scholar]
  4. Brown C. M., Herbert R. A. 1977a; Ammonia assimilation in purple and green sulphur bacteria. FEMS Microbiology Letters 1:39–42
    [Google Scholar]
  5. Brown C. M., Herbert R. A. 1977b; Ammonia assimilation in members of the Rhodospirillaceae . FEMS Microbiology Letters 1:43–46
    [Google Scholar]
  6. Carithers R. P., Yoch D. C., Arnon D. I. 1979; Two forms of nitrogenase from the photosynthetic bacterium Rhodospirillum rubrum . Journal of Bacteriology 137:779–789
    [Google Scholar]
  7. Gornall A. G., Bardawill C. J., David M. M. 1949; Determination of serum proteins by means of the biuret reaction. Journal of Biological Chemistry 177:751–760
    [Google Scholar]
  8. HemmilÄ I. A., MÄntsÄlÄ P. I. 1978; Purification and properties of glutamate synthase and glutamate dehydrogenase from Bacillus megaterium . Biochemical Journal 173:45–52
    [Google Scholar]
  9. Herbert R. A., Siefert E., Pfenning N. 1978; Nitrogen assimilation in Rhodopseudomonas acidophila . Archives of Microbiology 119:1–5
    [Google Scholar]
  10. Johansson B. C., Gest H. 1976; Inorganic nitrogen assimilation by the photosynthetic bacterium Rhodopseudomonas capsulata . Journal of Bacteriology 128:683–688
    [Google Scholar]
  11. Johansson B. C., Gest H. 1977; Adenylylation/deadenylylation control of the glutamine synthetase of Rhodopseudomonas capsulata . European Journal of Biochemistry 81:365–371
    [Google Scholar]
  12. Jones B. L., Monty K. J. 1979; Glutamine as a feedback inhibitor of the Rhodopseudomonas sphaeroides nitrogenase system. Journal of Bacteriology 139:1007–1013
    [Google Scholar]
  13. Keister D. L., Yike N. J. 1967; Energy-linked reactions in photosynthetic bacteria. II. The energy- dependent reduction of oxidized nicotinamide- adenine dinucleotide phosphate by reduced nicotinamide-adenine dinucleotide in chroma- top hores of Rhodospirillum rubrum . Biochemistry 6:3847–3857
    [Google Scholar]
  14. Ludden P. W., Burris R. H. 1976; Activating factor for the iron protein of nitrogenase from Rhodospirillum rubrum . Science 194:424–427
    [Google Scholar]
  15. Martin R. G., Ames B. N. 1961; A method of determining the sedimentation behavior of enzymes: application to protein mixtures. Journal of Biological Chemistry 236:1372–1379
    [Google Scholar]
  16. Miller R. E., Stadtman E. R. 1972; Glutamate synthase from Escherichia coli. Iron-sulfide flavo-protein. Journal of Biological Chemistry 247:7407–7419
    [Google Scholar]
  17. Nagatani H., Shimizu M., Valentine R. C. 1971; The mechanism of ammonia assimilation in nitrogen fixing bacteria. Archiv für Mikrobiologie 79:164–175
    [Google Scholar]
  18. Neilson A. H., Nordlund S. 1975; Regulation of nitrogenase synthesis in intact cells of Rhodospirillum rubrum: inactivation of nitrogen fixation by ammonia, l-glutamine and l-asparagine. Journal of General Microbiology 91:53–62
    [Google Scholar]
  19. Ormerod J. G., Ormerod K. S., Gest H. 1961; Light-dependent utilization of organic compounds and photoproduction of molecular hydrogen by photosynthetic bacteria; relationships with nitrogen metabolism. Archives of Biochemistry and Biophysics 94:449–463
    [Google Scholar]
  20. Trotta P. P., Platzer K. E. B., Haschemeyer R. H., Meister A. 1974; Glutamine-binding subunit of glutamate synthase and partial reactions catalysed by this glutamine amidotransferase. Proceedings of the National Academy of Sciences of the United States of America 71:4607–4611
    [Google Scholar]
  21. Wall J. D., Gest H. 1979; Derepression of nitrogenase activity in glutamine auxotrophs of Rhodopseudomonas capsulata . Journal of Bacteriology 137:1459–1463
    [Google Scholar]
  22. Weare N. M. 1978; The photoproduction of H2 and NH4 + fixed from N2 by a derepressed mutant of Rhodospirillum rubrum . Biochimica et biophysica acta 502:486–494
    [Google Scholar]
  23. Weare N. M., Shanmugam K. T. 1976; Photoproduction of ammonium from N2 in Rhodospirillum rubrum . Archives of Microbiology 110:207–213
    [Google Scholar]
  24. Yelton M. M. 1980 M.S. thesis University of South Carolina, Columbia, U.S.A.:
  25. Yoch D. C. 1979; Manganese, an essential trace element for N2 fixation by Rhodospirillum rubrum and Rhodopseudomonas capsulata: role in nitrogenase regulation. Journal of Bacteriology 140:987–995
    [Google Scholar]
  26. Yoch D. C. 1980; Regulation of nitrogenase A and R concentrations in Rhodopseudomonas capsulata by glutamine synthetase. Biochemical Journal 187:273–276
    [Google Scholar]
  27. Yoch D. C., Pengra R. M. 1966; Effect of amino acids on the nitrogenase system of Klebsiella pneumoniae . Journal of Bacteriology 92:618–622
    [Google Scholar]
http://instance.metastore.ingenta.com/content/journal/micro/10.1099/00221287-123-2-335
Loading
/content/journal/micro/10.1099/00221287-123-2-335
Loading

Data & Media loading...

Most cited this month Most Cited RSS feed

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