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Nitrification
''Nitrification'' is the biological oxidation of ammonia to nitrite followed by the oxidation of the nitrite to nitrate occurring through separate organisms or direct ammonia oxidation to nitrate in comammox bacteria. The transformation of ammonia to nitrite is usually the rate limiting step of nitrification. Nitrification is an important step in the nitrogen cycle in soil. Nitrification is an aerobic process performed by small groups of autotrophic bacteria and archaea. Microbiology Ammonia oxidation The oxidation of ammonia into nitrite (also known as nitritation) is performed by two groups of organisms, ammonia-oxidizing bacteria (AOB) and ammonia-oxidizing archaea (AOA). AOB AOB can be found among the Betaproteobacteria and Gammaproteobacteria. Since discovery of AOA in 2005, two isolates have been cultivated: ''Nitrosopumilus maritimus'' and ''Nitrososphaera viennensis''. In soils the most studied AOB belong to the genera '' Nitrosomonas'' and '' Nitroco ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nitrosomonas
''Nitrosomonas'' is a genus of Gram-negative bacteria, belonging to the Betaproteobacteria. It is one of the five genera of ammonia-oxidizing bacteria and, as an obligate chemolithoautotroph, uses ammonia (NH3) as an energy source and carbon dioxide (CO2) as a carbon source in presence of oxygen. ''Nitrosomonas'' are important in the global biogeochemical nitrogen cycle, since they increase the bioavailability of nitrogen to plants and in the denitrification, which is important for the release of nitrous oxide, a powerful greenhouse gas. This microbe is photophobic, and usually generate a biofilm matrix, or form clumps with other microbes, to avoid light. ''Nitrosomonas'' can be divided into six lineages: the first one includes the species '' Nitrosomonas europea'', ''Nitrosomonas eutropha'', ''Nitrosomonas halophila'', and ''Nitrosomonas mobilis.'' The second lineage presents the species ''Nitrosomonas communis'', ''N. sp. I'' and ''N. sp. II,'' meanwhile the third lineage inclu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nitrifying Bacteria
Nitrifying bacteria are chemolithotrophic organisms that include species of genera such as '' Nitrosomonas'', ''Nitrosococcus'', '' Nitrobacter'', '' Nitrospina'', '' Nitrospira'' and '' Nitrococcus''. These bacteria get their energy from the oxidation of inorganic nitrogen compounds. Types include ammonia-oxidizing bacteria (AOB) and nitrite-oxidizing bacteria (NOB). Many species of nitrifying bacteria have complex internal membrane systems that are the location for key enzymes in nitrification: ammonia monooxygenase (which oxidizes ammonia to hydroxylamine), hydroxylamine oxidoreductase (which oxidizes hydroxylamine to nitric oxide - which is further oxidized to nitrite by a currently unidentified enzyme), and nitrite oxidoreductase (which oxidizes nitrite to nitrate). Ecology Nitrifying bacteria are present in distinct taxonomical groups and are found in highest numbers where considerable amounts of ammonia are present (such as areas with extensive protein decomposition, and sewa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nitrogen Cycle
The nitrogen cycle is the biogeochemical cycle by which nitrogen is converted into multiple chemical forms as it circulates among atmospheric, terrestrial, and marine ecosystems. The conversion of nitrogen can be carried out through both biological and physical processes. Important processes in the nitrogen cycle include fixation, ammonification, nitrification, and denitrification. The majority of Earth's atmosphere (78%) is atmospheric nitrogen, making it the largest source of nitrogen. However, atmospheric nitrogen has limited availability for biological use, leading to a scarcity of usable nitrogen in many types of ecosystems. The nitrogen cycle is of particular interest to ecologists because nitrogen availability can affect the rate of key ecosystem processes, including primary production and decomposition. Human activities such as fossil fuel combustion, use of artificial nitrogen fertilizers, and release of nitrogen in wastewater have dramatically altered the global n ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nitrogen Cycle
The nitrogen cycle is the biogeochemical cycle by which nitrogen is converted into multiple chemical forms as it circulates among atmospheric, terrestrial, and marine ecosystems. The conversion of nitrogen can be carried out through both biological and physical processes. Important processes in the nitrogen cycle include fixation, ammonification, nitrification, and denitrification. The majority of Earth's atmosphere (78%) is atmospheric nitrogen, making it the largest source of nitrogen. However, atmospheric nitrogen has limited availability for biological use, leading to a scarcity of usable nitrogen in many types of ecosystems. The nitrogen cycle is of particular interest to ecologists because nitrogen availability can affect the rate of key ecosystem processes, including primary production and decomposition. Human activities such as fossil fuel combustion, use of artificial nitrogen fertilizers, and release of nitrogen in wastewater have dramatically altered the global n ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bacteria
Bacteria (; singular: bacterium) are ubiquitous, mostly free-living organisms often consisting of one biological cell. They constitute a large domain of prokaryotic microorganisms. Typically a few micrometres in length, bacteria were among the first life forms to appear on Earth, and are present in most of its habitats. Bacteria inhabit soil, water, acidic hot springs, radioactive waste, and the deep biosphere of Earth's crust. Bacteria are vital in many stages of the nutrient cycle by recycling nutrients such as the fixation of nitrogen from the atmosphere. The nutrient cycle includes the decomposition of dead bodies; bacteria are responsible for the putrefaction stage in this process. In the biological communities surrounding hydrothermal vents and cold seeps, extremophile bacteria provide the nutrients needed to sustain life by converting dissolved compounds, such as hydrogen sulphide and methane, to energy. Bacteria also live in symbiotic and parasitic r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crenarchaeol
Crenarchaeol is a glycerol biphytanes glycerol tetraether (GDGT) biological membrane lipid. Together with archaeol, crenarcheol comprises a major component of archaeal membranes. Archaeal membranes are distinct from those of bacteria and eukaryotes because they contain isoprenoid GDGTs instead of diacyl lipids, which are found in the other domains (bacteria, procarya). It has been proposed that GDGT membrane lipids are an adaptation to the high temperatures present in the environments that are home to extremophile archaea Discovery and distribution Archaeal GDGTs were first detected in pelagic waters. Unknown GDGTs were also found in marine sediments and isolated from '' Cenarchaeum symbiosum'', a marine ammonia-oxidizing archaeon that lives in symbiosis with sponges. Following the discovery of GDGTs outside of hydrothermal environments, crenarchaeol was first identified as the major GDGT component in surface sediments and extracts from ''C. symbiosum'' by two-dimensional nuc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Comammox
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. 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. Complete conversion of ammonia into nitrate by a single microorganism was first predicted in 2006. 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. Within the genus ''Nitrospira,'' the major ecosystems comammox are primarily found in natural aquifers and engineered ecosystems. 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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nitrate
Nitrate is a polyatomic ion with the chemical formula . Salts containing this ion are called nitrates. Nitrates are common components of fertilizers and explosives. Almost all inorganic nitrates are soluble in water. An example of an insoluble nitrate is bismuth oxynitrate. Structure The ion is the conjugate base of nitric acid, consisting of one central nitrogen atom surrounded by three identically bonded oxygen atoms in a trigonal planar arrangement. The nitrate ion carries a formal charge of −1. This charge results from a combination formal charge in which each of the three oxygens carries a − charge, whereas the nitrogen carries a +1 charge, all these adding up to formal charge of the polyatomic nitrate ion. This arrangement is commonly used as an example of resonance. Like the isoelectronic carbonate ion, the nitrate ion can be represented by resonance structures: Dietary nitrate A rich source of inorganic nitrate in the human diets come from leafy green foo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Achille Müntz
Charles Achille Müntz (10 August 1846 – 20 February 1917) was a French agricultural chemist. Biography He was born at Soultz-sous-Forêts, Alsace, studied under Jean-Baptiste Boussingault in Paris, and, after acting as his assistant for ten years, succeeded him as director of the chemical laboratories in the Institut National Agronomique (1887–1914). From 1907 to 1914 he was also director of the research station for plant chemistry at Meudon (Collège de France).MÜNTZ Charles Achille Sociétés savantes de France He was a member of the (1896–1917) and the |
Jean-Jacques Schloesing
Jean-Jacques is a French name, equivalent to "John James" in English. Since the second half of 18th century, Jean Jacques Rousseau was widely known as Jean Jacques. Notable people bearing this name include: Given name * Jean-Jacques Annaud (born 1943), French film director, screenwriter and producer * John James Audubon, born Jean-Jacques Rabin (1785–1851), American ornithologist and painter from Breton origin * Jean-Jacques Bertrand (1916–1973), Premier of Quebec, Canada * Jean-Jacques Burnel (born 1952), Franco-English musician, bassist * Jean-Jacques Challet-Venel (1811–1893), member of the Swiss Federal Council * Jean-Jacques Colin (1784-1865), French chemist * Jean-Jacques Conceição (born 1964), Angolan basketball player * Jean-Jacques De Gucht (born 1983), Flemish politician and member of Open VLD * Jean-Jacques Dessalines (1758–1806), a leader of the Haïtian Revolution * Jean-Jacques Domoraud (born 1981), Côte d'Ivoire footballer * Jean-Jacques Goldman (born 1951), ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nitrospinota
Nitrospinota is a bacterial phylum. Despite only few described species, members of this phylum are major nitrite-oxidizing bacteria in surface waters in oceans. By oxidation of nitrite to nitrate they are important in the process of nitrification in marine environments. Although genus Nitrospina is aerobic bacterium, it was shown to oxidize nitrite also in oxygen minimum zone of the ocean. Depletion of oxygen in such zones leads to preference of anaerobic processes such as denitrification and nitrogen loss through anammox. Nitrospina thus outweight nitrogen loss by nitrification also in these oxygen depleted zones. Among the cultivated isolates within the genus ''Nitrospina'' are '' Nitrospina gracilis'' and '' Nitrospina watsonii''. Further genomes were resolved by culture-independent metagenome binning. The two ''Nitrospina'' species are, however, distantly related to environmentally abundant uncultured Nitrospinota. The two other strains were cultivated in 2020 each in the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alexander Müller (chemist)
Alexander or Alex Müller may refer to: * K. Alex Müller (born 1927), Swiss physicist and Nobel laureate * Alex Müller (racing driver) Alexander Müller (born 20 January 1979) is a German racing driver. Career Müller stepped up from karting in 1995, and finished third in BMW Formula Junior driving for Abt Sportsline. In 1996 he won Formula Renault Germany. Müller stepped up ... (born 1979), German racing driver * Alexander Müller (skeleton racer), Austrian skeleton racer * Alexander Müller (composer) (1808–1863), German pianist, teacher, conductor and composer * Alexander Müller (politician) (born 1969), German politician * Alexander Müller (chemist) (1828–1906), German agricultural chemist {{hndis, Muller, Alexander ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
