Biological Nitrogen Removal Database
A manually curated data resource for microbial nitrogen removal
Biological Nitrogen Removal Database
A manually curated data resource for microbial nitrogen removal
Influent:Real wastewater
Comammox System:Sequential batch reactor coupling anammox and n-DAMO
reactor:Sequential batch reactor (SBR)
Medium:Suspended-sludge
Culture taken from:Freshwater lake sediment
Microorganism cultured:n-DAMO archaea and n-DAMO bacteria
Respiration:Anaerobic
Electron donor:Methane
Electron acceptor:Nitrite
PH:7.3
Temperature:25–30?°C
HRT:nan
NH4–N Influent conc(mg/L):nan
NO2–N Influent conc(mg/L):nan
NO3–N Influent conc(mg/L):nan
NH4–N Effluent (mg N/L):nan
NO2–N Effluent (mg N/L):nan
NO3-N Effluent (mg N/L):nan
NH4–N removal rate mg/L/d:82.9
NO2–N removal rate mg/L/d:160.0
NO3-N removal rate mg/L/d:17
TN Removal rate (mg N/L/d):nan
Authors:Ettwig et al., 2010
Title:Nitrite-driven anaerobic methane oxidation by oxygenic bacteria
Pubmed link:None
Full research link:Link
Abstract:Only three biological pathways are known to produce oxygen: photosynthesis, chlorate respiration and the detoxification of reactive oxygen species. Here we present evidence for a fourth pathway, possibly of considerable geochemical and evolutionary importance. The pathway was discovered after metagenomic sequencing of an enrichment culture that couples anaerobic oxidation of methane with the reduction of nitrite to dinitrogen. The complete genome of the dominant bacterium, named ‘Candidatus Methylomirabilis oxyfera’, was assembled. This apparently anaerobic, denitrifying bacterium encoded, transcribed and expressed the well-established aerobic pathway for methane oxidation, whereas it lacked known genes for dinitrogen production. Subsequent isotopic labelling indicated that ‘M. oxyfera’ bypassed the denitrification intermediate nitrous oxide by the conversion of two nitric oxide molecules to dinitrogen and oxygen, which was used to oxidize methane. These results extend our understanding of hydrocarbon degradation under anoxic conditions and explain the biochemical mechanism of a poorly understood freshwater methane sink. Because nitrogen oxides were already present on early Earth, our finding opens up the possibility that oxygen was available to microbial metabolism before the evolution of oxygenic photosynthesis.