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Nitrifying and denitrifying pathways of methanotrophic bacteria
1Department of Biological Sciences, University of Alberta, Edmonton, AB, Canada. lisa.stein@ualberta.ca
Biochemical Society Transactions
|November 23, 2011
Summary
Nitrous oxide, a potent greenhouse gas, accumulates due to human activities. Aerobic methanotrophic bacteria offer insights into nitrogen oxide production and cycling, impacting environmental nitrogen levels.
Area of Science:
- Environmental Science
- Microbiology
- Biogeochemistry
Background:
- Nitrous oxide (N2O) is a significant greenhouse gas and ozone-depleting substance.
- Anthropogenic activities and land-use changes drive atmospheric N2O accumulation.
- Nitrogen oxides are key intermediates in nitrification and denitrification processes.
Purpose of the Study:
- To investigate the role of aerobic methanotrophic bacteria in nitrogen oxide metabolism.
- To explore the enzymatic pathways involved in nitrogen oxide production and reduction.
- To understand how methanotrophs influence environmental nitrogen cycling.
Main Methods:
- Analysis of microbial genome sequences to identify enzymes in nitrogen oxide pathways.
- Comparative genomics to understand evolutionary relatedness to ammonia-oxidizing bacteria.
- Investigating the dual nitrification and denitrification capabilities of methanotrophs.
Main Results:
- Methanotrophs possess extensive enzymatic machinery for nitrogen oxide metabolism.
- These bacteria exhibit both nitrification and denitrification, independent of growth requirements.
- Evolutionary links to ammonia-oxidizing bacteria contribute to their nitrogen oxide processing capabilities.
Conclusions:
- Aerobic methanotrophic bacteria are crucial for understanding diverse nitrogen oxide production mechanisms.
- Their metabolic flexibility impacts environmental N2O abundance and the balance of nitrogen and methane cycles.
- Understanding methanotrophs is vital for mitigating greenhouse gas emissions.
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