Nitrifying bacteria

Nitrifying bacteria

Nitrifying bacteria are chemoautotrophic or chemolithotrophs depending on the genera (Nitrosomonas, Nitrosococcus, Nitrobacter, Nitrococcus) bacteria that grow by consuming inorganic nitrogen compounds.[1] 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, and nitrite oxidoreductase, which oxidizes nitrite to nitrate.

Contents

Ecology

Nitrifying bacteria are widespread in soil and water, and are found in highest numbers where considerable amounts of ammonia are present (areas with extensive protein decomposition, and sewage treatment plants).[2] Nitrifying bacteria thrive in lakes and streams with high inputs of sewage and wastewater because of the high ammonia content.

Oxidation of ammonia to nitrate

Nitrification in nature is the result of actions of two groups of organisms, the nitrosifyers (ammonia-oxidizing bacteria) and nitrifying bacteria (nitrite-oxidizing, nitrate producing bacteria)[3]

Nitrosifying bacteria

NH3 + O2 + 2H+ + 2e− → NH2OH +  H2O (1.1)
NH2OH +  H2O → NO−
2 + 5H+ + 4e− (1.2) +
NH3 + O2 → NO−
2 + 3H+ + 2e− (1)

Nitrifying bacteria

NO−
2 +  H2O → NO−
3 + 2H+ + 2e− (2)
Nitrifying bacteria that oxidize ammonia (nitrosifyers)
Characteristics Genus Phylogenetic group DNA (mol% GC) Habitats
Gram-negative short to long rods, motile (polar flagella)or nonmotile; peripheral membrane systems Nitrosomonas Beta 45-53 Soil, Sewage, freshwater, Marine
Large cocci, motile, vesicular or peripheral membranes Nitrosococcus Gamma 49-50 Freshwater, Marine
Spirals, motile (peritrichous flagella); no obvious membrane system Nitrosospira Beta 54 Soil
Pleomorphic, lobular, compartmented cells; motile (peritrichous flagella) Nitrosolobus Beta 54 Soil
Nitrifying bacteria that oxidize nitrite
Characteristics Genus Phylogenetic group DNA (mol% GC) Habitats
Short rods, reproduce by budding, occasionally motile (single subterminal flagella) or non-motile; membrane system arranged as a polar cap Nitrobacter Alpha 59-62 Soil, Freshwater, Marine
Long, slender rods, nonmotile, no obvious membrane system Nitrospina Delta 58 Marine
Large Cocci, motile (one or two subterminal flagellum) membrane system randomly arranged in tubes Nitrococcus Gamma 61 Marine
Helical to vibroid-shaped cells; nonmotile; no internal membranes Nitrospira Nitrospirae 50 Marine, Soil

See also

References

  1. ^ Mancinelli RL (1996). "The nature of nitrogen: an overview". Life support & biosphere science : international journal of earth space 3 (1–2): 17–24. PMID 11539154. 
  2. ^ Belser LW (1979). "Population ecology of nitrifying bacteria". Annu. Rev. Microbiol. 33: 309–333. doi:10.1146/annurev.mi.33.100179.001521. PMID 386925. 
  3. ^ Ward BB (1996). "Nitrification and ammonification in aquatic systems". Life support & biosphere science : international journal of earth space 3 (1–2): 25–9. PMID 11539155. 

Wikimedia Foundation. 2010.

Игры ⚽ Поможем написать курсовую

Look at other dictionaries:

  • nitrifying bacteria — Small group of oxygen requiring bacteria that use nitrogen as an energy source. These microorganisms are important in the nitrogen cycle as converters of soil ammonia to nitrates, compounds usable by plants. The nitrification process requires two …   Universalium

  • nitrifying bacteria — nitrifikatoriai statusas T sritis ekologija ir aplinkotyra apibrėžtis Nitritinės (Nitrosomonas genties) ir nitratinės (Nitrobacter genties) bakterijos, paverčiančios amonio druskas nitratais. atitikmenys: angl. nitrifiers; nitrifying bacteria vok …   Ekologijos terminų aiškinamasis žodynas

  • nitrifying bacteria — nitrobakterijos statusas T sritis ekologija ir aplinkotyra apibrėžtis Nitritinės ir nitratinės bakterijos, oksiduojančios nitritus ir nitratus. atitikmenys: angl. nitrifying bacteria; nitrobacteria vok. Nitrobakterien, f rus. нитробактерии …   Ekologijos terminų aiškinamasis žodynas

  • nitrifying bacteria — noun plural Date: 1925 bacteria of a family (Nitrobacteraceae) comprising gram negative bacteria commonly found in the soil and obtaining energy through the process of nitrification …   New Collegiate Dictionary

  • nitrifying bacteria — (ni trī fi ing) Chemolithotrophic, gram negative bacteria that are members of the family Nitrobacteriaceae and convert ammonia to nitrate and nitrite to nitrate …   Dictionary of microbiology

  • bacteria — bacterial, adj. bacterially, adv. /bak tear ee euh/, n.pl., sing. bacterium / tear ee euhm/. ubiquitous one celled organisms, spherical, spiral, or rod shaped and appearing singly or in chains, comprising the Schizomycota, a phylum of the kingdom …   Universalium

  • nitrifying bacterium — plural  Nitrifying Bacteria,        any of a small group of aerobic bacteria (family Nitrobacteraceae) that use inorganic chemicals as an energy source. They are microorganisms that are important in the nitrogen cycle as converters of soil… …   Universalium

  • nitrifying — ni·tri·fy·ing nī trə .fī iŋ adj active in nitrification <nitrifying bacteria> * * * ni·tri·fy·ing (niґtrĭ fi″ing) oxidizing ammonia to nitrite (nitrosification) and then to nitrate …   Medical dictionary

  • Bacteria — Taxobox color = lightgrey name = Bacteria fossil range = Archean or earlier Recent image width = 210px image caption = Escherichia coli image is 8 micrometres wide. domain = Bacteria subdivision ranks = Phyla [cite web… …   Wikipedia

  • nitrifying — adjective Describing certain bacteria that oxidize ammonia to nitrite and nitrate in the soil …   Wiktionary

Share the article and excerpts

Direct link
… Do a right-click on the link above
and select “Copy Link”