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. 1987 Apr;169(4):1632–1638. doi: 10.1128/jb.169.4.1632-1638.1987

Ammonium and methylammonium transport in Rhodobacter sphaeroides.

M L Cordts, J Gibson
PMCID: PMC211992  PMID: 2881920

Abstract

Rhodobacter sphaeroides maintained intracellular ammonium pools of 1.1 to 2.6 mM during growth in several fixed nitrogen sources as well as during diazotrophic growth. Addition of 0.15 mM NH4+ to washed, nitrogen-free cell suspensions was followed by linear uptake of NH4+ from the medium and transient formation of intracellular pools of 0.9 to 1.5 mM NH4+. Transport of NH4+ was shown to be independent of assimilation by glutamine synthetase because intracellular pools of over 1 mM represented NH4+ concentration gradients of at least 100-fold across the cytoplasmic membrane. Ammonium pools of over 1 mM were also found in non-growing cell suspensions in nitrogen-free medium after glutamine synthetase was inhibited with methionine sulfoximine. In NH4+-free cell suspensions, methylammonium (14CH3NH3+) was taken up rapidly, and intracellular concentrations of 0.4 to 0.5 mM were maintained. The 14CH3NH3+ pool was not affected by methionine sulfoximine. Unlike NH4+ uptake, 14CH3NH3+ uptake in nitrogen-free cell suspensions was repressed by growth in NH4+. These results suggest that R. sphaeroides may produce an NH4+-specific transport system in addition to the NH4+/14CH3NH3+ transporter. This second transporter is able to produce normal-size NH4+ pools but has very little affinity for 14CH3NH3+ and is not repressed by growth in high concentrations of NH4+.

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Selected References

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  1. Barnes E. M., Jr, Zimniak P., Jayakumar A. Role of glutamine synthetase in the uptake and metabolism of methylammonium by Azotobacter vinelandii. J Bacteriol. 1983 Nov;156(2):752–757. doi: 10.1128/jb.156.2.752-757.1983. [DOI] [PMC free article] [PubMed] [Google Scholar]
  2. Barnes E. M., Jr, Zimniak P. Transport of ammonium and methylammonium ions by Azotobacter vinelandii. J Bacteriol. 1981 May;146(2):512–516. doi: 10.1128/jb.146.2.512-516.1981. [DOI] [PMC free article] [PubMed] [Google Scholar]
  3. Bellion E., Wayland L. Methylamine uptake in Pseudomonas species strain MA: utilization of methylamine as the sole nitrogen source. J Bacteriol. 1982 Jan;149(1):395–398. doi: 10.1128/jb.149.1.395-398.1982. [DOI] [PMC free article] [PubMed] [Google Scholar]
  4. Boussiba S., Dilling W., Gibson J. Methylammonium transport in Anacystis nidulans R-2. J Bacteriol. 1984 Oct;160(1):204–210. doi: 10.1128/jb.160.1.204-210.1984. [DOI] [PMC free article] [PubMed] [Google Scholar]
  5. 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: 10.1006/abio.1976.9999. [DOI] [PubMed] [Google Scholar]
  6. Drozd J. W., Tubb R. S., Postgate J. R. A chemostat study of the effect of fixed nitrogen sources on nitrogen fixation, membranes and free amino acids in Azotobacter chroococcum. J Gen Microbiol. 1972 Nov;73(2):221–232. doi: 10.1099/00221287-73-2-221. [DOI] [PubMed] [Google Scholar]
  7. Gaensslen R. E., McCarty R. E. Determination of solute accumulation in chloroplasts by rapid centrifugal transfer through silicone fluid layers. Anal Biochem. 1972 Aug;48(2):504–514. doi: 10.1016/0003-2697(72)90105-4. [DOI] [PubMed] [Google Scholar]
  8. Gober J. W., Kashket E. R. Methylammonium uptake by Rhizobium sp. strain 32H1. J Bacteriol. 1983 Mar;153(3):1196–1201. doi: 10.1128/jb.153.3.1196-1201.1983. [DOI] [PMC free article] [PubMed] [Google Scholar]
  9. Gordon J. K., Moore R. A. Ammonium and methylammonium transport by the nitrogen-fixing bacterium Azotobacter vinelandii. J Bacteriol. 1981 Nov;148(2):435–442. doi: 10.1128/jb.148.2.435-442.1981. [DOI] [PMC free article] [PubMed] [Google Scholar]
  10. Jayakumar A., Epstein W., Barnes E. M., Jr Characterization of ammonium (methylammonium)/potassium antiport in Escherichia coli. J Biol Chem. 1985 Jun 25;260(12):7528–7532. [PubMed] [Google Scholar]
  11. Kalb V. F., Jr, Donohue T. J., Corrigan M. G., Bernlohr R. W. A new and specific assay for ammonia and glutamine sensitive to 100 pmol. Anal Biochem. 1978 Oct 1;90(1):47–57. doi: 10.1016/0003-2697(78)90007-6. [DOI] [PubMed] [Google Scholar]
  12. Kleiner D., Alef K., Hartmann A. Uptake of methionine sulfoximine by some N2 fixing bacteria, and its effect on ammonium transport. FEBS Lett. 1983 Nov 28;164(1):121–123. doi: 10.1016/0014-5793(83)80032-5. [DOI] [PubMed] [Google Scholar]
  13. Kleiner D. Ammonium uptake by nitrogen fixing bacteria I. Azotobacter vinelandii. Arch Microbiol. 1975 Jun 22;104(2):163–169. doi: 10.1007/BF00447319. [DOI] [PubMed] [Google Scholar]
  14. Kleiner D. Energy expenditure for cyclic retention of NH3/NH4+ during N2 fixation by Klebsiella pneumoniae. FEBS Lett. 1985 Aug 5;187(2):237–239. doi: 10.1016/0014-5793(85)81249-7. [DOI] [PubMed] [Google Scholar]
  15. Kobayashi H. Second system for potassium transport in Streptococcus faecalis. J Bacteriol. 1982 May;150(2):506–511. doi: 10.1128/jb.150.2.506-511.1982. [DOI] [PMC free article] [PubMed] [Google Scholar]
  16. ROSEN H. A modified ninhydrin colorimetric analysis for amino acids. Arch Biochem Biophys. 1957 Mar;67(1):10–15. doi: 10.1016/0003-9861(57)90241-2. [DOI] [PubMed] [Google Scholar]
  17. SISTROM W. R. A requirement for sodium in the growth of Rhodopseudomonas spheroides. J Gen Microbiol. 1960 Jun;22:778–785. doi: 10.1099/00221287-22-3-778. [DOI] [PubMed] [Google Scholar]
  18. Schreier H. J., Smith T. M., Bernlohr R. W. Regulation of nitrogen catabolic enzymes in Bacillus spp. J Bacteriol. 1982 Aug;151(2):971–975. doi: 10.1128/jb.151.2.971-975.1982. [DOI] [PMC free article] [PubMed] [Google Scholar]
  19. Turpin D. H., Edie S. A., Canvin D. T. In Vivo Nitrogenase Regulation by Ammonium and Methylamine and the Effect of MSX on Ammonium Transport in Anabaena flos-aquae. Plant Physiol. 1984 Mar;74(3):701–704. doi: 10.1104/pp.74.3.701. [DOI] [PMC free article] [PubMed] [Google Scholar]

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