Microbial Ecology

, Volume 65, Issue 1, pp 180–196 | Cite as

The Ammonia Transport, Retention and Futile Cycling Problem in Cyanobacteria

Physiology and Biotechnology

Abstract

Ammonia is the preferred nitrogen source for many algae including the cyanobacterium Synechococcus elongatis (Synechococcus R-2; PCC 7942). Modelling ammonia uptake by cells is not straightforward because it exists in solution as NH3 and NH4+. NH3 is readily diffusible not only via the lipid bilayer but also through aquaporins and other more specific porins. On the other hand, NH4+ requires cationic transporters to cross a membrane. Significant intracellular ammonia pools (≈1–10 mol m−3) are essential for the synthesis of amino acids from ammonia. The most common model envisaged for how cells take up ammonia and use it as a nitrogen source is the “pump–leak model” where uptake occurs through a simple diffusion of NH3 or through an energy-driven NH4+ pump balancing a leak of NH3 out of the cell. The flaw in such models is that cells maintain intracellular pools of ammonia much higher than predicted by such models. With caution, [14C]-methylamine can be used as an analogue tracer for ammonia and has been used to test various models of ammonia transport and metabolism. In this study, simple “proton trapping” accumulation by the diffusion of uncharged CH3NH2 has been compared to systems where CH3NH3+ is taken up through channels, driven by the membrane potential (ΔUi,o) or the electrochemical potential for Na+μNai,o+). No model can be reconciled with experimental data unless the permeability of CH3NH2 across the cell membrane is asymmetric: permeability into the cell is very high through gated porins, whereas permeability out of the cell is very low (≈40 nm s−1) and independent of the extracellular pH. The best model is a Nain+/CH3NH3+in co-porter driven by ΔμNai,o+ balancing synthesis of methylglutamine and a slow leak governed by Ficks law, and so there is significant futile cycling of methylamine across the cell membrane to maintain intracellular methylamine pools high enough for fixation by glutamine synthetase. The modified pump–leak model with asymmetric permeability of the uncharged form is a viable model for understanding ammonia uptake and retention in plants, free-living microbes and organisms in symbiotic relationships.

Abbreviations

A

An amine of general formula R–NH2 in the uncharged form

BIS-TRIS-PROPANE

1,3-Bis[tris(hydroxymethyl)methylamino]propane

CAPS

3-(Cyclohexylamino)-1-propanesulfonic acid

HA+

An amine (R-NH2) in the charged form R–NH3+

MES

4-Morpholineethanesulphonic acid

PA

Permeability of an uncharged amine (R–NH2)

PHA+

Permeability of an amine cation (R–NH3+)

PNH3

Permeability of NH3 across cell membrane at a specified pH

PMA

Permeability of CH3NH2 across cell membrane at a specified pH

PNH4+

Goldman permeability of NH4+ across the cell membrane

PMA+

Goldman permeability of CH3NH3+ across the cell membrane

PPFD

Photosynthetic photon fluence density (400–700 nm)

i (subscript)

Refers to the inside of the cells

o (subscript)

Refers to the outside of the cells or bulk electrolyte

ΔUi,o

The membrane potential gradient inside vs. outside

ΔμNai,o+

The sodium motive force or sodium electrochemical potential

References

  1. 1.
    Ritchie RJ, Gibson J (1987) Permeability of ammonia, methylamine and ethylamine in the cyanobacterium, Synechococcus R-2 (Anacystis nidulans) PCC 7942. J Membr Biol 95:131–142CrossRefGoogle Scholar
  2. 2.
    Kaneko T, Sato S, Kotani H, Tanaka A, Asamizu E, Nakamura Y et al (1996) Sequence analysis of the genome of the unicellular cyanobacterium Synechocystis sp. strain PCC6803. II. Sequence determination of the entire genome and assignment of potential protein-coding regions. DNA Res 3:109–136PubMedCrossRefGoogle Scholar
  3. 3.
    Kaneko T, Sato S, Kotani H, Tanaka A, Asamizu E, Nakamura Y et al (1996) Sequence analysis of the genome of the unicellular cyanobacterium Synechocystis sp. strain PCC6803. II. Sequence determination of the entire genome and assignment of potential protein-coding regions (supplement). DNA Res 3:185–209PubMedCrossRefGoogle Scholar
  4. 4.
    Nakamura Y, Kaneko T, Hirosawa M, Miyajima N, Tabata S (1998) CyanoBase, a www database containing the complete nucleotide sequence of the genome of Synechocystis sp. strain PCC6803. Nucleic Acids Res 26:63–67PubMedCrossRefGoogle Scholar
  5. 5.
    Kamin H (ed) (1979) Ammonia—National Research Council. Subcommittee on Ammonia. University Park, BaltimoreGoogle Scholar
  6. 6.
    Kleiner D (1985) Bacterial ammonium transport. FEMS Microbiol Rev 32:87–100CrossRefGoogle Scholar
  7. 7.
    Neijssel OM, Buurman ET, Teixeira de Mattos MJ (1990) The role of futile cycles in the energetics of bacterial growth. Biochim Biophys Acta 1018:252–255PubMedCrossRefGoogle Scholar
  8. 8.
    Kennedy IR, Pereg-Gerk LL, Wood CC, Deaker R, Gilchrist K, Katupitiya S (1997) Biological nitrogen fixation in non-leguminous field crops: facilitating the evolution of an effective association between Azospirillum and wheat. Plant Soil 194:65–79CrossRefGoogle Scholar
  9. 9.
    Boussiba S, Dilling W, Gibson J (1984) Methylammonium transport in Anacystis nidulans. J Bacteriol 160:204–210PubMedGoogle Scholar
  10. 10.
    Collander R (1954) The permeability of Nitella cells to non-electrolytes. Physiol Plant 7:420–445CrossRefGoogle Scholar
  11. 11.
    Walter A, Gutknecht J (1986) Permeability of small non-electrolytes through lipid bilayer membranes. J Membr Biol 90:207–217PubMedCrossRefGoogle Scholar
  12. 12.
    Nobel PS (2004) Physicochemical and environmental plant physiology, 3rd edn. Elsevier, BostonGoogle Scholar
  13. 13.
    Murata K, Mitsuoka F, Hirai T, Walz T, Agre P, Heymann JB, Engel A, Fujiyoshi Y (2000) Structural determinants of water permeation through aquaporin-1. Nature 407:599–605PubMedCrossRefGoogle Scholar
  14. 14.
    Ludewig U, Neuhauser B, Dynowski M (2007) Molecular mechanisms of ammonium transport and accumulation in plants. FEBS Lett 581:2301–2308PubMedCrossRefGoogle Scholar
  15. 15.
    Maurel C (2007) Plant aquaporins: novel functions and regulation properties. FEBS Lett 581:227–2236CrossRefGoogle Scholar
  16. 16.
    CyanoBase (2011) http://genome.kazusa.or.jp/cyanobase. Accessed 18 May 2011
  17. 17.
    Labotka RJ, Lundberg P, Kuchel PW (1995) Ammonia permeability of erythrocyte membrane studied by 14N and 15N saturation transfer NMR spectroscopy. Am J Physiol 268:C686–C699PubMedGoogle Scholar
  18. 18.
    Niemietz CM, Tyerman SD (2000) Channel-mediated permeation of ammonia gas through the peribacteroid membrane of soybean nodules. FEBS Lett 465:110–114PubMedCrossRefGoogle Scholar
  19. 19.
    Kikeri D, Sun A, Zeidel ML, Hebert SC (1989) Cell membranes impermeable to NH3. Nature 339:478–480PubMedCrossRefGoogle Scholar
  20. 20.
    Priver NA, Rabon EC, Zeidel ML (1993) Apical membrane of the gastric parietal wall: water, proton and non-electrolyte permeabilities. Biochemistry 32:2459–2468PubMedCrossRefGoogle Scholar
  21. 21.
    Walsby AE (1985) The permeability of heterocysts to the gases nitrogen and oxygen. Proc R Soc B Biol Sci 226:345–366CrossRefGoogle Scholar
  22. 22.
    Van Dommelen A, Keijers V, Vanderleyden J, de Zamaroczy M (1998) (Methyl)ammonium transport in the nitrogen-fixing bacterium Azospirillum brasilense. J Bacteriol 180:2652–2659PubMedGoogle Scholar
  23. 23.
    Ritchie RJ, Islam N (2001) Permeability of methylamine across the cell membrane of a cyanobacterial cell. New Phytol 152:203–212CrossRefGoogle Scholar
  24. 24.
    Soupene E, He L, Yan D, Kustu S (1998) Ammonia acquisition in enteric bacteria: physiological role of the ammonium/methylammonium transport B (amtB) protein. Proc Natl Acad Sci U S A 95:7030–7034PubMedCrossRefGoogle Scholar
  25. 25.
    Gruswitz F, O’Connell J, Stroud RM (2007) Inhibitory complex of the transmembrane ammonia channel, AmtB, and the cytosolic regulatory protein, GlnK, at 1.96 Å. Proc Natl Acad Sci U S A 104:42–47PubMedCrossRefGoogle Scholar
  26. 26.
    Mayer M, Dynowski M, Ludewig U (2006) Ammonium ion transport by the AMT/Rh homologue LeAMT1;1. Biochem J 396:431–437PubMedCrossRefGoogle Scholar
  27. 27.
    Tyerman SD, Whitehead LF, Day DA (1995) A channel-like transporter for NH4+ on the symbiotic interface of N2 fixing plants. Nature 378:629–632CrossRefGoogle Scholar
  28. 28.
    Udvardi MA, Day DA (1997) Metabolite transport across symbiotic membranes in root nodules. Annu Rev Plant Physiol 48:493–523CrossRefGoogle Scholar
  29. 29.
    Britto DT, Siddiqi MY, Glass ADM, Kronzucker HJ (2001) Futile transmembrane NH4+ cycling: a cellular hypothesis to explain ammonium toxicity in plants. Proc Natl Acad Sci U S A 98:4255–4258PubMedCrossRefGoogle Scholar
  30. 30.
    O’Hara GW, Riley IT, Glenn AR, Dilworth MJ (1985) The ammonium permease of Rhizobium leguminosarum MNF3841. J Gen Physiol 131:757–764Google Scholar
  31. 31.
    Ritchie RJ (1987) The permeabilities of amines in Chara corallina (australis), (Charophyta). J Exp Bot 38:67–76CrossRefGoogle Scholar
  32. 32.
    Ritchie RJ, Gibson J (1987) Permeability of ammonia and amines in Rhodobacter sphaeroides and Bacillus firmus. Arch Biochem Biophys 258:332–341PubMedCrossRefGoogle Scholar
  33. 33.
    Ritchie RJ, Nadolny C, Larkum AWD (1996) Driving forces for bicarbonate transport in the cyanobacterium Synechococcus R-2 (Anacystis nidulans, S. leopoliensis) PCC 7942. Plant Physiol 112:1573–1584PubMedGoogle Scholar
  34. 34.
    Ritchie RJ, Trautman DA, Larkum AWD (1997) Phosphate uptake in the cyanobacterium Synechococcus R-2 PCC 7942. Plant Cell Physiol 38:1232–1241CrossRefGoogle Scholar
  35. 35.
    Ritchie RJ (1998) Bioenergetics of membrane transport in Synechococcus R-2 (Anacystis nidulans, S. leopoliensis) PCC 7942. Can J Bot 76:1127–1145Google Scholar
  36. 36.
    Lindsay WL (1979) Chemical equilibria in soils. Wiley-Interscience, New YorkGoogle Scholar
  37. 37.
    Boussiba S, Gibson J (1987) Regulation of methylammonium/ammonium transport in the unicellular cyanobacterium Synechococcus R-2 (PCC 7942). FEMS Microbiol Lett 43:289–293CrossRefGoogle Scholar
  38. 38.
    Walker NA, Smith FA, Beilby MJ (1979) Amine uniport at the plasmalemma of charophyte cells. II. Ratio of matter to charge transported and permeability of free base. J Membr Biol 49:283–296CrossRefGoogle Scholar
  39. 39.
    Merrick MJ, Edwards RA (1995) Nitrogen control in bacteria. Microbiol Rev 59:604–622PubMedGoogle Scholar
  40. 40.
    KEGG (2011) (Kyoto Encyclopedia of Genes and Genomes). http://www.genome.ad.jp/kegg. Accessed 22 May 2011
  41. 41.
    Morris JG (1970) A biologist’s physical chemistry. Edward Arnold, LondonGoogle Scholar
  42. 42.
    Ritchie RJ (1992) Sodium transport and the origin of the membrane potential in the cyanobacterium Synechococcus R-2 (Anacystis nidulans) PCC 7942. J Plant Physiol 139:320–330CrossRefGoogle Scholar
  43. 43.
    Allen MM (1968) Simple conditions for growth of unicellular blue-green algae. J Phycol 4:1–3CrossRefGoogle Scholar
  44. 44.
    Ritchie RJ (1991) Membrane potential and pH control in the cyanobacterium Synechococcus R-2 (Anacystis nidulans) PCC 7942. J Plant Physiol 137:409–418CrossRefGoogle Scholar
  45. 45.
    Johnson ML, Faunt LM (1992) Parameter estimation by least-squares methods. Method Enzymol 210:1–37CrossRefGoogle Scholar
  46. 46.
    Zar JH (1984) Biostatistical analysis. Prentice Hall, Englewood CliffsGoogle Scholar
  47. 47.
    Aylward G, Findlay T (1993) SI chemical data. Wiley, BrisbaneGoogle Scholar
  48. 48.
    Ritchie RJ (1997) Rubidium transport in the cyanobacterium Synechococcus R-2 (Anacystis nidulans, S. leopoliensis) PCC 7942. Plant Cell Environ 20:907–918CrossRefGoogle Scholar
  49. 49.
    Ritchie RJ, Larkum AWD (1998) Uptake of thallium, a toxic heavy metal, in the cyanobacterium Synechococcus R-2 (Anacystis nidulans, S. leopoliensis) PCC 7942. Plant Cell Physiol 39:1156–1168CrossRefGoogle Scholar
  50. 50.
    Cordts M, Gibson J (1987) Ammonium and methylammonium transport in Rhodobacter sphaeroides. J Bacteriol 169:1632–1638PubMedGoogle Scholar
  51. 51.
    Atkins GL (1969) Multicompartment models for biological systems. Methuen, LondonGoogle Scholar
  52. 52.
    von Wiren N, Merrick M (2004) Regulation and function of ammonium carriers in bacteria, fungi and plants. Top Curr Genet 9:95–120CrossRefGoogle Scholar
  53. 53.
    Tömroth-Horsefield S, Wang Y, Hedfalk K, Johanson U, Karlsson M, Tajkhorshid E, Neutze R, Kjellbom P (2006) Structural mechanism of plant aquaporin gating. Nature 439:688–694CrossRefGoogle Scholar
  54. 54.
    Ortiz-Ramerez C, Mora SI, Trejo J, Pantoja O (2011) PvAMT1;1, a highly selective ammonium transporter that functions as a H+/NH4+ symporter. J Biol Chem 286:31113–31122CrossRefGoogle Scholar
  55. 55.
    Marcus Y (1988) Ionic radii in aqueous solutions. Chem Rev 88:1475–1498CrossRefGoogle Scholar
  56. 56.
    Ritchie RJ, Trautman DA, Larkum AWD (2001) Phosphate-limited cultures of the cyanobacterium Synechococcus R-2 (PCC 7942) are capable of very rapid, opportunistic uptake of phosphate. New Phytol 152:189–202CrossRefGoogle Scholar
  57. 57.
    Orr J, Hazelkorn R (1981) Kinetic and inhibition studies of glutamine synthetase from the cyanobacterium Anabaena 7120. J Biol Chem 256:13099–13104PubMedGoogle Scholar
  58. 58.
    Florencio FJ, Ramos JL (1985) Purification and characterization of glutamine synthetase from the unicellular cyanobacterium Anacystis nidulans. Biochim Biophys Acta 838:39–48CrossRefGoogle Scholar
  59. 59.
    Merida A, Leurentop L, Candau P, Florencio FJ (1990) Purification and properties of glutamine synthetases from the cyanobacteria Synechocystis sp. strain PCC 6803 and Calothrix sp. strain PCC 7601. J Bacteriol 172:4732–4735PubMedGoogle Scholar

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© Springer Science+Business Media, LLC 2012

Authors and Affiliations

  1. 1.Faculty of Technology & EnvironmentPrince of Songkla University—Phuket CampusKathuThailand

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