Back to Search
Start Over
Cultivation of an obligate acidophilic ammonia oxidizer from a nitrifying acid soil.
- Source :
-
Proceedings of the National Academy of Sciences of the United States of America [Proc Natl Acad Sci U S A] 2011 Sep 20; Vol. 108 (38), pp. 15892-7. Date of Electronic Publication: 2011 Sep 06. - Publication Year :
- 2011
-
Abstract
- Nitrification is a fundamental component of the global nitrogen cycle and leads to significant fertilizer loss and atmospheric and groundwater pollution. Nitrification rates in acidic soils (pH < 5.5), which comprise 30% of the world's soils, equal or exceed those of neutral soils. Paradoxically, autotrophic ammonia oxidizing bacteria and archaea, which perform the first stage in nitrification, demonstrate little or no growth in suspended liquid culture below pH 6.5, at which ammonia availability is reduced by ionization. Here we report the discovery and cultivation of a chemolithotrophic, obligately acidophilic thaumarchaeal ammonia oxidizer, "Candidatus Nitrosotalea devanaterra," from an acidic agricultural soil. Phylogenetic analysis places the organism within a previously uncultivated thaumarchaeal lineage that has been observed in acidic soils. Growth of the organism is optimal in the pH range 4 to 5 and is restricted to the pH range 4 to 5.5, unlike all previously cultivated ammonia oxidizers. Growth of this organism and associated ammonia oxidation and autotrophy also occur during nitrification in soil at pH 4.5. The discovery of Nitrosotalea devanaterra provides a previously unsuspected explanation for high rates of nitrification in acidic soils, and confirms the vital role that thaumarchaea play in terrestrial nitrogen cycling. Growth at extremely low ammonia concentration (0.18 nM) also challenges accepted views on ammonia uptake and metabolism and indicates novel mechanisms for ammonia oxidation at low pH.
- Subjects :
- Acids chemistry
Archaea genetics
Archaea growth & development
Bacteria genetics
Bacteria growth & development
Bacteria metabolism
DNA, Archaeal chemistry
DNA, Archaeal genetics
Ecosystem
Hydrogen-Ion Concentration
In Situ Hybridization, Fluorescence
Microscopy, Electron, Scanning
Molecular Sequence Data
Nitrification
Nitrites metabolism
Oxidation-Reduction
Phylogeny
RNA, Ribosomal, 16S genetics
Sequence Analysis, DNA
Ammonia metabolism
Archaea metabolism
Soil analysis
Soil Microbiology
Subjects
Details
- Language :
- English
- ISSN :
- 1091-6490
- Volume :
- 108
- Issue :
- 38
- Database :
- MEDLINE
- Journal :
- Proceedings of the National Academy of Sciences of the United States of America
- Publication Type :
- Academic Journal
- Accession number :
- 21896746
- Full Text :
- https://doi.org/10.1073/pnas.1107196108