Skip to main content
NCBI home page
Applied and Environmental Microbiology logoLink to Applied and Environmental Microbiology
. 1995 Aug;61(8):2970–2975. doi: 10.1128/aem.61.8.2970-2975.1995

Halotolerance of the Phototrophic Bacterium Rhodobacter capsulatus E1F1 Is Dependent on the Nitrogen Source

M I Igeno, C G del Moral, F Castillo, F J Caballero
PMCID: PMC1388552  PMID: 16535098

Abstract

Phototrophic growth of the moderate halotolerant Rhodobacter capsulatus strain E1F1 in media containing up to 0.3 M NaCl was dependent on the nitrogen source used. In these media, increased growth rates and growth levels were observed in the presence of reduced nitrogen sources such as ammonium and amino acids. When the medium contained an oxidized nitrogen source (dinitrogen or nitrate), increases in salinity severely inhibited phototrophic growth. However, the addition of glycine betaine promoted halotolerance and allowed the cells to grow in 0.2 M NaCl. Inhibition of diazotrophic growth by salinity was due to a decrease in nitrogenase activity which was no longer synthesized and reversibly inactivated, both effects being alleviated by the addition of glycine betaine. In R. capsulatus E1F1, inhibition of cell growth in nitrate by salt was due to a rapid inhibition of nitrate uptake, which led to a long-term decrease in nitrate reductase activity, probably caused by repression of the enzyme. Addition of glycine betaine immediately restored nitrate uptake, but the recovery of nitrate reductase activity required several hours. Neither ammonium uptake nor ammonium assimilation through the glutamine synthetase-glutamate synthase pathway was affected by NaCl.

Full Text

The Full Text of this article is available as a PDF (293.6 KB).

Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. Abee T., Palmen R., Hellingwerf K. J., Konings W. N. Osmoregulation in Rhodobacter sphaeroides. J Bacteriol. 1990 Jan;172(1):149–154. doi: 10.1128/jb.172.1.149-154.1990. [DOI] [PMC free article] [PubMed] [Google Scholar]
  2. Bradford M. M. A rapid and sensitive method for the quantitation of microgram quantities of protein utilizing the principle of protein-dye binding. Anal Biochem. 1976 May 7;72:248–254. doi: 10.1016/0003-2697(76)90527-3. [DOI] [PubMed] [Google Scholar]
  3. Caballero F. J., Cejudo F. J., Florencio F. J., Cárdenas J., Castillo F. Molecular and regulatory properties of glutamine synthetase from the phototrophic bacterium Rhodopseudomonas capsulata E1F1. J Bacteriol. 1985 May;162(2):804–809. doi: 10.1128/jb.162.2.804-809.1985. [DOI] [PMC free article] [PubMed] [Google Scholar]
  4. Caballero F. J., Cárdenas J., Castillo F. Purification and properties of L-alanine dehydrogenase of the phototrophic bacterium Rhodobacter capsulatus E1F1. J Bacteriol. 1989 Jun;171(6):3205–3210. doi: 10.1128/jb.171.6.3205-3210.1989. [DOI] [PMC free article] [PubMed] [Google Scholar]
  5. Csonka L. N., Hanson A. D. Prokaryotic osmoregulation: genetics and physiology. Annu Rev Microbiol. 1991;45:569–606. doi: 10.1146/annurev.mi.45.100191.003033. [DOI] [PubMed] [Google Scholar]
  6. Fernandes T. A., Iyer V., Apte S. K. Differential responses of nitrogen-fixing cyanobacteria to salinity and osmotic stresses. Appl Environ Microbiol. 1993 Mar;59(3):899–904. doi: 10.1128/aem.59.3.899-904.1993. [DOI] [PMC free article] [PubMed] [Google Scholar]
  7. Gouesbet G., Abaibou H., Wu L. F., Mandrand-Berthelot M. A., Blanco C. Osmotic repression of anaerobic metabolic systems in Escherichia coli. J Bacteriol. 1993 Jan;175(1):214–221. doi: 10.1128/jb.175.1.214-221.1993. [DOI] [PMC free article] [PubMed] [Google Scholar]
  8. Imhoff J. F., Rodriguez-Valera F. Betaine is the main compatible solute of halophilic eubacteria. J Bacteriol. 1984 Oct;160(1):478–479. doi: 10.1128/jb.160.1.478-479.1984. [DOI] [PMC free article] [PubMed] [Google Scholar]
  9. Kranz R. G., Haselkorn R. Characterization of nif regulatory genes in Rhodopseudomonas capsulata using lac gene fusions. Gene. 1985;40(2-3):203–215. doi: 10.1016/0378-1119(85)90043-5. [DOI] [PubMed] [Google Scholar]
  10. Laemmli U. K. Cleavage of structural proteins during the assembly of the head of bacteriophage T4. Nature. 1970 Aug 15;227(5259):680–685. doi: 10.1038/227680a0. [DOI] [PubMed] [Google Scholar]
  11. Madigan M. T., Wall J. D., Gest H. Dark anaerobic dinitrogen fixation by a photosynthetic microorganism. Science. 1979 Jun 29;204(4400):1429–1430. doi: 10.1126/science.204.4400.1429. [DOI] [PubMed] [Google Scholar]
  12. Madkour M. A., Smith L. T., Smith G. M. Preferential osmolyte accumulation: a mechanism of osmotic stress adaptation in diazotrophic bacteria. Appl Environ Microbiol. 1990 Sep;56(9):2876–2881. doi: 10.1128/aem.56.9.2876-2881.1990. [DOI] [PMC free article] [PubMed] [Google Scholar]
  13. Meyer J., Kelley B. C., Vignais P. M. Effect of light nitrogenase function and synthesis in Rhodopseudomonas capsulata. J Bacteriol. 1978 Oct;136(1):201–208. doi: 10.1128/jb.136.1.201-208.1978. [DOI] [PMC free article] [PubMed] [Google Scholar]
  14. Molenaar D., Hagting A., Alkema H., Driessen A. J., Konings W. N. Characteristics and osmoregulatory roles of uptake systems for proline and glycine betaine in Lactococcus lactis. J Bacteriol. 1993 Sep;175(17):5438–5444. doi: 10.1128/jb.175.17.5438-5444.1993. [DOI] [PMC free article] [PubMed] [Google Scholar]
  15. Márquez F. J., Quesada A. R., Sánchez-Jiménez F., Núez de Castro I. Determination of 27 dansyl amino acid derivatives in biological fluids by reversed-phase high-performance liquid chromatography. J Chromatogr. 1986 Aug 2;380(2):275–283. doi: 10.1016/s0378-4347(00)83656-7. [DOI] [PubMed] [Google Scholar]
  16. Reddy B. R., Apte S. K., Thomas J. Enhancement of cyanobacterial salt tolerance by combined nitrogen. Plant Physiol. 1989 Jan;89(1):204–210. doi: 10.1104/pp.89.1.204. [DOI] [PMC free article] [PubMed] [Google Scholar]
  17. Smith L. T., Pocard J. A., Bernard T., Le Rudulier D. Osmotic control of glycine betaine biosynthesis and degradation in Rhizobium meliloti. J Bacteriol. 1988 Jul;170(7):3142–3149. doi: 10.1128/jb.170.7.3142-3149.1988. [DOI] [PMC free article] [PubMed] [Google Scholar]
  18. Yancey P. H., Clark M. E., Hand S. C., Bowlus R. D., Somero G. N. Living with water stress: evolution of osmolyte systems. Science. 1982 Sep 24;217(4566):1214–1222. doi: 10.1126/science.7112124. [DOI] [PubMed] [Google Scholar]
  19. Zumft W. G., Castillo F. Regulatory properties of the nitrogenase from Rhodopseudomonas palustris. Arch Microbiol. 1978 Apr 27;117(1):53–60. doi: 10.1007/BF00689351. [DOI] [PubMed] [Google Scholar]

Articles from Applied and Environmental Microbiology are provided here courtesy of American Society for Microbiology (ASM)

RESOURCES