Regulation of Inorganic Nitrogen Metabolism in the Phototrophic Bacterium Rhodobacter Capsulatus E1F1

  • C. Moreno-Vivián
  • F. J. Caballero
  • M. Martínez-Luque
  • J. Cárdenas
  • F. Castillo


The phototrophic bacterium Rhodobacter capsulatus E1F1 utilizes oxidized, inorganic nitrogen compounds such as dinitrogen, nitrate or nitrite, as well as reduced nitrogen sources such as amino acids, urea or ammonium for phototrophic growth. Although nitrogen fixation is wide-spread among Rhodospirillaceae, only few strains are able to reduce and/or assimilate nitrate (Ferguson et al. 1987). R. capsulatus E1F1 reduces nitrate (Moreno-Vivian et al. 1982) and nitrite (Kerber et al. 1981) to ammonium only under anaerobic conditions in the light and exhibits an ammonium-sensitive nitrate reductase (Moreno-Vivian et al. 1982). Ammonium is also the end product of nitrogen fixation, a process regulated by light intensity, nitrogen compounds and oxygen. In R. capsulatus E1F1, assimilation of ammonium derived from nitrate or dinitrogen reduction takes place mainly by the GS/GOGAT cycle (Moreno-Vivian et al. 1983), and the nitrogen flux through this pathway is regulated at the level of both glutamine synthetase activity (Caballero et al. 1985) and synthesis (Caballero et al. 1989 b).


Nitrogen Fixation Glutamine Synthetase Nitrate Uptake Glutamine Synthetase Activity Nitrate Assimilation 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



alanine dehydrogenase






glutamate synthase


glycine:oxaloacetate aminotransferase


aspartate aminotransferase


glutamine synthetase






nitrate reductase


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. Arp DJ, Zumft WG (1983) L-methionine-SR-sulfoximine as a probe for the role of glutamine synthetase in nitrogenase switch-off by ammonia and glutamine in Rhodopseudomonas palustris. Arch Microbiol 134: 17–22PubMedCrossRefGoogle Scholar
  2. Caballero FJ, Cejudo FJ, Florencio FJ, Cárdenas J, Castillo F (1985) Molecular and regulatory properties of glutamine synthetase from the phototrophic bacterium Rhodopomonas capsulate E1F1. J Bacteriol 162: 804–809PubMedGoogle Scholar
  3. Caballero FJ, Moreno-Vivian C, Castillo F, Cárdenas J (1986) Nitrite uptake system in photosynthetic bacterium Rhodopseudomonas capsulata E1F1. Biochim Biophys Acta 848: 16–23CrossRefGoogle Scholar
  4. Caballero FJ, Cárdenas J, Castillo F (1989 a) Purification and properties of L-alanine dehydrogenase of the phototrophic bacteriumRhodobacter capsulatus E1F1. J. bacteriol 171: 3205–3210PubMedGoogle Scholar
  5. Caballero FJ, Igeño MI, Cárdenas J, Castillo F (1989 b) Regulation of reduced nitrogen assimilation in Rhodobacter capsulatus E1F1. Arch Microbiol (in press)Google Scholar
  6. Ferguson SJ, Jackson JB, McEwan AG (1987) Anaerobic respiration in the Rhodospirillaceae: Characterization of pathways and evaluation of roles in redox balancing during photosynthesis. FEMS Microbiol Rev 46: 117–143CrossRefGoogle Scholar
  7. Johansson BC, Gest H (1976) Inorganic nitrogen assimilation by the photosynthetic bacterium Rhodopseudomonas capsulata. J Bacteriol 128: 683–688PubMedGoogle Scholar
  8. Jouanneau Y, Meyer C, Vignais PM (1988) Regulation of nitrogenase activity in Rhodobacter capsulatus: ADP-ribosylation of the Fe protein. In: Bothe H, de Bruijn FJ, Newton WE (eds) Nitrogen Fixation: Hundred Years After. Gustav Fischer, Stuttgart New York, pp 173Google Scholar
  9. Kanemoto RH, Ludden PW (1984) Effect of ammonia, darkness and phenazine methosulfate on whole-cell nitrogenase activity and Fe protein modification in Rhodospirillum rubrum. J Bacteriol 158: 713–720PubMedGoogle Scholar
  10. Kerber NL, Caballero FJ, Cardenas J (1981) Assimilatory nitrite reductase from Rhodopseudomonas capsulata E1F1. FEMS Microbiol Lett 11: 249–252CrossRefGoogle Scholar
  11. Moreno-Vivian C, Castillo F, Cardenas J (1982) Effect of light and darkness on nitrate assimilation by Rhodopseudomonas capsulata E1F1. Photosynth Res 3: 313–319CrossRefGoogle Scholar
  12. Moreno-Vivian C, Cejudo FJ, Cardenas J, Castillo F (1983) Ammonia assimilation pathways in Rhodopseudomonas capsulate E1F1. Arch Microbiol 136: 147–151CrossRefGoogle Scholar
  13. Moreno-Vivian C, Cardenas J, Castillo F (1986) In vivo short-term inhibition of nitrogenase by nitrate in Rhodopseudomonas capsulata E1F1. FEMS Microbiol Lett 34: 105–109Google Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 1990

Authors and Affiliations

  • C. Moreno-Vivián
  • F. J. Caballero
  • M. Martínez-Luque
  • J. Cárdenas
  • F. Castillo
    • 1
  1. 1.Departamento de Bioquímica, Biología Molecular y FisiologíaFacultad de Ciencias, Universidad de CórdobaCórdobaSpain

Personalised recommendations