Influent:Real wastewater
Comammox System:Sequential batch reactor coupling anammox and n-DAMO
reactor:Sequential batch reactor (SBR)
Medium:Suspended-sludge
Culture taken from:Enriched n-DAMO and anammox culture
Microorganism cultured:n-DAMO archaea and n-DAMO bacteria
Respiration:Anaerobic
Electron donor:Methane
Electron acceptor:Nitrite
PH:7.3–7.8
Temperature:35°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:10
NO2–N removal rate mg/L/d:nan
NO3-N removal rate mg/L/d:2
TN Removal rate (mg N/L/d):nan
Authors:Daims et al., 2015
Title:Complete nitrification by Nitrospira bacteria
Pubmed link:None
Full research link:Link
Abstract:Nitrification, the oxidation of ammonia via nitrite to nitrate, has always been considered to be a two-step process catalysed by chemolithoautotrophic microorganisms oxidizing either ammonia or nitrite. No known nitrifier carries out both steps, although complete nitrification should be energetically advantageous. This functional separation has puzzled microbiologists for a century. Here we report on the discovery and cultivation of a completely nitrifying bacterium from the genus Nitrospira, a globally distributed group of nitrite oxidizers. The genome of this chemolithoautotrophic organism encodes the pathways both for ammonia and nitrite oxidation, which are concomitantly activated during growth by ammonia oxidation to nitrate. Genes affiliated with the phylogenetically distinct ammonia monooxygenase and hydroxylamine dehydrogenase genes of Nitrospira are present in many environments and were retrieved on Nitrospira-contigs in new metagenomes from engineered systems. These findings fundamentally change our picture of nitrification and point to completely nitrifying Nitrospira as key components of nitrogen-cycling microbial communities.