Methanoperedens nitroreducens

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Methanoperedens nitroreducens
Scientific classification OOjs UI icon edit-ltr.svg
Domain: Archaea
Kingdom: Methanobacteriati
Phylum: Halobacteriota
Class: Methanomicrobia
Order: Methanosarcinales
Family: Methanoperedenaceae
Genus: Methanoperedens
Species:
M. nitroreducens
Binomial name
Methanoperedens nitroreducens
Haroon et al. 2013

Methanoperedens nitroreducens (from Latin: methano, meaning "methane", peredens, meaning "consuming", nitro, meaning "nitrate", and reducens, meaning "leading back") is a candidate species of methanotrophic archaea that oxidizes methane by coupling to nitrate reduction. [1]

Contents

Morphology

M. nitroreducens are irregular cocci with a diameter of 1-3 μm. [2]

Metabolism

Ideal conditions for M. nitroreducens growth consist of temperatures around 72–95 °F (22–35 °C) and neutral to slightly basic pH of 7-8. [2] M. nitroreducens has been cultured in a bioreactor, but a pure culture has not yet been cultivated. [2]

M. nitroreducens is one of only two organisms that are currently known to be able to couple methane oxidation with nitrate or nitrite reduction, the other being Methylomirabilis oxyfera . M. nitroreducens utilizes the anaerobic oxidation of methane (AOM), [2] a process which serves as an important sink of environmental methane, lowering the gas' overall impact on climate change. [3] This process was originally discovered to be paired with sulfate reduction, but is now known to also be paired with nitrate and metal ion (Mn4+ or Fe3+) reduction. M. nitroreducens uses reverse methanogenesis with nitrate as the terminal electron acceptor. [2] [3]

M. nitroreducens is the first anaerobic methanotrophic archaea found to have genes for the full reverse methanogenesis pathway. [2] The full pathway of acetyl-CoA has also been found in M. nitroreducens. [3] It has been suggested that AOM is facilitated by Borgs, unusual large extrachromosomal DNA elements found in Methanoperedens. [4]

Ecology

M. nitroreducens survives in oxygen-free environments and can typically be found in deeper down in freshwater ecosystems. [1] [5] M. nitroreducens is more likely to exist and be competitive in an environment enriched in nitrate as opposed to sulfate or other potential terminal electron acceptors. [5] M. nitroreducens competes against other organisms who reduce nitrate with other carbon sources. [5]

Requiring both methane and nitrate, this organism is commonly found in the area between oxic and anoxic zones. [1] While originally known as an anaerobic species, [2] it has oxygen tolerance mechanisms. When it is in contact with oxygen, M. nitroreducens will up-regulate genes needed to protect against oxidative stress. [1] This differs from other anaerobic species who suffer irreversible damage when exposed to oxygen, [6] hinting at future applications for this archaeal species.

Discovery

M. nitroreducens was first described by Haroon et al. in 2013 after adding methane, ammonium, and nitrate to a bioreactor, which led to a single organism proliferating. [2]

References

  1. 1 2 3 4 Guerrero-Cruz, Simon; Cremers, Geert; van Alen, Theo A.; Op den Camp, Huub J. M.; Jetten, Mike S. M.; Rasigraf, Olivia; Vaksmaa, Annika (2018). "Response of the Anaerobic Methanotroph "Candidatus Methanoperedens nitroreducens" to Oxygen Stress". Applied and Environmental Microbiology. 84 (24): e01832–18. Bibcode:2018ApEnM..84E1832G. doi:10.1128/AEM.01832-18. PMC   6275348 . PMID   30291120.
  2. 1 2 3 4 5 6 7 8 Haroon, Mohamed F.; Hu, Shihu; Shi, Ying; Imelfort, Michael; Keller, Jurg; Hugenholtz, Philip; Yuan, Zhiguo; Tyson, Gene W. (August 2013). "Anaerobic oxidation of methane coupled to nitrate reduction in a novel archaeal lineage" . Nature. 500 (7464): 567–570. Bibcode:2013Natur.500..567H. doi:10.1038/nature12375. ISSN   1476-4687. PMID   23892779. S2CID   4368118.
  3. 1 2 3 Cui, Mengmeng; Ma, Anzhou; Qi, Hongyan; Zhuang, Xuliang; Zhuang, Guoqiang (February 2015). "Anaerobic oxidation of methane: an "active" microbial process". MicrobiologyOpen. 4 (1): 1–11. doi:10.1002/mbo3.232. ISSN   2045-8827. PMC   4335971 . PMID   25530008.
  4. Al-Shayeb, Basem; Schoelmerich, Marie C.; West-Roberts, Jacob; Valentin-Alvarado, Luis E.; Sachdeva, Rohan; Mullen, Susan; Crits-Christoph, Alexander; Wilkins, Michael J.; Williams, Kenneth H.; Doudna, Jennifer A.; Banfield, Jillian F. (2021-07-10). "Borgs are giant extrachromosomal elements with the potential to augment methane oxidation": 2021.07.10.451761. doi:10.1101/2021.07.10.451761.{{cite journal}}: Cite journal requires |journal= (help)
  5. 1 2 3 Lu, Peili; Liu, Tao; Ni, Bing-Jie; Guo, Jianhua; Yuan, Zhiguo; Hu, Shihu (2019-04-01). "Growth kinetics of Candidatus 'Methanoperedens nitroreducens' enriched in a laboratory reactor" . Science of the Total Environment. 659: 442–450. Bibcode:2019ScTEn.659..442L. doi:10.1016/j.scitotenv.2018.12.351. ISSN   0048-9697. PMID   31096374. S2CID   104422754.
  6. Kampman, Christel; Piai, Laura; Temmink, Hardy; Hendrickx, Tim L. G.; Zeeman, Grietje; Buisman, Cees J. N. (2018-05-14). "Effect of low concentrations of dissolved oxygen on the activity of denitrifying methanotrophic bacteria". Water Science and Technology. 77 (11): 2589–2597. doi: 10.2166/wst.2018.219 . ISSN   0273-1223. PMID   29944124.