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Updated: Jun 25, 2026
08:05
Measurement of the Potential Rates of Dissimilatory Nitrate Reduction to Ammonium Based on 14NH4+/15NH4+ Analyses via Sequential Conversion to N2O
Published on: October 7, 2020
Ammonia-oxidizing archaea involved in nitrogen removal
Jia You1, Atreyee Das, Elizabeth M Dolan
1Department of Civil and Environmental Engineering, University of Missouri, Columbia, MO 65211, USA.
Water Research
|February 24, 2009
Summary
Ammonia oxidation, vital for nitrogen cycling, is now known to involve both ammonia-oxidizing bacteria (AOB) and ammonia-oxidizing archaea (AOA). The discovery of AOA in diverse environments highlights their significant ecological roles.
Area of Science:
- Environmental microbiology
- Biogeochemical cycles
- Nitrogen cycling
Background:
- Ammonia oxidation is a key step in the global nitrogen cycle.
- Traditionally, ammonia-oxidizing bacteria (AOB) were considered the sole drivers of this process.
- Recent discoveries reveal ammonia-oxidizing archaea (AOA) also play a crucial role.
Purpose of the Study:
- To describe the nitrogen cycle, ammonia oxidation processes, and the organisms involved.
- To highlight the significance of ammonia-oxidizing archaea (AOA) in various ecosystems.
- To explore the application of molecular tools in studying AOB and AOA.
Main Methods:
- Literature review of nitrogen cycling and ammonia oxidation.
- Description of ammonia-oxidizing organisms, including the isolated Candidatus "Nitrosopumilus maritimus".
- Discussion of molecular tools used for studying ammonia-oxidizing bacteria (AOB) and archaea (AOA) abundance and community structure.
Main Results:
- Ammonia oxidation involves both AOB and AOA.
- AOA, like Candidatus "Nitrosopumilus maritimus", possess genes for ammonia monooxygenase.
- AOA are widespread in diverse habitats and may outnumber AOB in some environments.
- AOA presence in activated sludge suggests a role in wastewater treatment.
Conclusions:
- The perception of ammonia oxidation being solely driven by bacteria is outdated.
- AOA are significant players in ammonia oxidation across various ecosystems.
- Further research into AOA is needed to fully understand their ecological roles, particularly in wastewater treatment and nitrogen removal.
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