Comammox

Add links
Source: Wikipedia, the free encyclopedia.

Comammox (COMplete AMMonia OXidation) is the name attributed to an organism that can convert ammonia into nitrite and then into nitrate through the process of nitrification.[1] Nitrification has traditionally thought to be a two-step process, where ammonia-oxidizing bacteria and archaea oxidize ammonia to nitrite and then nitrite-oxidizing bacteria convert to nitrate.[2][3] Complete conversion of ammonia into nitrate by a single microorganism was first predicted in 2006.[1] In 2015 the presence of microorganisms that could carry out both conversion processes was discovered within the genus Nitrospira, and the nitrogen cycle was updated.[4][5] Within the genus Nitrospira, the major ecosystems comammox are primarily found in natural aquifers and engineered ecosystems.[6]

Complete nitrification step yield more energy (∆G°′ = −349 kJ mol−1 NH3) than either single oxidation alone (∆G°′ = −275 kJ mol−1 NH3 for ammonia oxidation to nitrite and ∆G°′ = −74 kJ mol−1 NO2− for nitrite oxidation to nitrate).[5]

Comammox Nitrospira Bacteria

Complete nitrification of oxidizing ammonia to nitrate is energetically advantageous for

nitrifier has a high affinity for ammonia, slow growth rate, low maximum rate of ammonia oxidation, and high yield.[7][6] The discovery of comammox Nitrospira provides a view into the modular evolution of the nitrogen cycle and expands upon the complexity of the evolutionary history of nitrification.[5]

Ecosystem of Comammox

Comammox have been identified in many ecosystems, including natural

ammonia-oxidizing bacteria and/or archaea, and in some cases outnumber other ammonia-oxidizing prokaryotes.[3][6][8][9] The ecosystem of comammox is currently unknown in terms of biogeography, including their distribution and abundance, due to the influences of process configuration and chemical composition of the treated wastewater.[3][6] Following these findings, it was determined that comammox may out-select canonical nitrite oxidizing bacteria in the genus Nitrospira in some engineered environments, suggesting the potentially important role for comammox in efficient biological nitrogen removal in wastewater treatment processes.[3]

See also

References

  1. ^
    PMID 16621570
    .
  2. ^ Winogradsky, Serge (1892). "Contributions a la morphologie des organismes de la nitrification". Arch. Sci. Biol. 1: 87–137.
  3. ^
    PMID 29414055
    .
  4. PMID 26610025
    .
  5. ^
    PMID 26610024
    .
  6. ^
    S2CID 4325672
    .
  7. ^
    PMID 28847001
    .
  8. ISSN 0043-1354
    .
  9. ISSN 0043-1354
    .
Retrieved from "https://en.wikipedia.org/w/index.php?title=Comammox&oldid=1208844287"