Nitrosomonas europaea: Difference between revisions
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Enter summaries of the most recent research here--at least three required | Enter summaries of the most recent research here--at least three required | ||
The dynamics of growth and death of immobilized Nitrosomonas europaea were studied. For this, the death rate of suspended cells was determined in the absence of ammonium or oxygen by following the loss of respiration activity and by fluorescein-diacetate (FDA)/ lissamine-green staining techniques. The death rates obtained (1.06 x 10[-6] s[-1] or 4.97 x 10[-6] s[-1] in the absence of oxygen or ammonium, respectively) were incorporated in a dynamic growth model and the effects on the performance of the immobilized-cell process illustrated by model simulations. These model simulations and experimental validation show that if decay of biomass occurs the biomass concentration in the center of the bead decreases. As a result, the systems react slower to changes in substrate concentrations than if all cells remain viable. | |||
==References== | ==References== | ||
Revision as of 18:14, 3 May 2007
A Microbial Biorealm page on the genus Nitrosomonas europaea
Classification
Higher order taxa
Domain; Phylum; Class; Order; family [Others may be used. Use NCBI link to find]
Domain: Prokaryota
Phylum: Proteobacteria
Class: Beta Proteobacteria
Order: Nitrosomonadales
Family: Nitrosomonadaceae
Genus: Nitrosomonas
Species: N. europea
Species
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NCBI: Taxonomy |
Nitrosomonas europaea
Description and significance
Describe the appearance, habitat, etc. of the organism, and why it is important enough to have its genome sequenced. Describe how and where it was isolated. Include a picture or two (with sources) if you can find them.
Nitrosomonas europaea is a Gram negative chemolithoautroph with the shape of bacillus. It is a nitrite oxidizing bacteria that lives in places rich in ammonia and inorganic salt, such as soil, sewage, freshwater, the walls of buildings and on the surface of monuments. It's often found in the polluted areas where the air contains high levels of nitrogen compounds.
It is important enough to have its genome sequenced because this organism plays a central role in the availability of nitrogen to plants and hence in limiting C02 fixation. These bacteria are important players in the treatment of industrial and sewage waste in the first step of oxidizing ammonia to nitrate. N. europaea is also capable of degrading a variety of halogenated organic compounds, including trichloroethylene , benzene and vinyl chloride, which may make it an attractive organism for bioremediation.
Genome structure
Describe the size and content of the genome. How many chromosomes? Circular or linear? Other interesting features? What is known about its sequence? Does it have any plasmids? Are they important to the organism's lifestyle?
Cell structure and metabolism
Describe any interesting features and/or cell structures; how it gains energy; what important molecules it produces.
Nitrosomonas europaea is an autotroph. It can obtain the carbon that it needs to grow by getting it from the atmosphere in a process known as "carbon fixation". Carbon fixation is the process of converting carbon in a gaseous form into carbon bound up in organic molecules. This bacterium contains "carboxysomes" (dark spots which can be seen scattered throughout the cell), which store the enzymes used to fix carbon dioxide for cell carbon.
Ecology
Describe any interactions with other organisms (included eukaryotes), contributions to the environment, effect on environment, etc.
This nitrifying bacterium is the most studied of the ammonia-oxidizing bacteria that are participants in the biogeochemical N cycle. Nitrifying bacteria play a central role in the availability of nitrogen to plants and hence in limiting CO2 fixation. The reaction catalyzed by these bacteria is the first step in the oxidation of ammonia to nitrate. N.europaea also is capable of degrading a variety of halogenated organic compounds, including trichloroethylene, benzene, and vinyl chloride. The ability of nitrifying organisms to degrade some pollutants may make these organisms attractive for controlled bioremediation in nitrifying soils and waters.
Pathology
How does this organism cause disease? Human, animal, plant hosts? Virulence factors, as well as patient symptoms.
Application to Biotechnology
Does this organism produce any useful compounds or enzymes? What are they and how are they used?
Conversion of ammonia to dinitrogen in wastewater was tried by Nitrosomonas europaea because Nitrosomonas europaea contains ammonia-oxidizing enzyme, nitrite reductase, and nitrous oxide reductase.
Current Research
Enter summaries of the most recent research here--at least three required
The dynamics of growth and death of immobilized Nitrosomonas europaea were studied. For this, the death rate of suspended cells was determined in the absence of ammonium or oxygen by following the loss of respiration activity and by fluorescein-diacetate (FDA)/ lissamine-green staining techniques. The death rates obtained (1.06 x 10[-6] s[-1] or 4.97 x 10[-6] s[-1] in the absence of oxygen or ammonium, respectively) were incorporated in a dynamic growth model and the effects on the performance of the immobilized-cell process illustrated by model simulations. These model simulations and experimental validation show that if decay of biomass occurs the biomass concentration in the center of the bead decreases. As a result, the systems react slower to changes in substrate concentrations than if all cells remain viable.
References
- Patrick Chain et al. (May 2003). "Complete Genome Sequence of the Ammonia-Oxidizing Bacterium and Obligate Chemolithoautotroph Nitrosomonas europaea". Journal of Bacteriology 185: 2759-2773.
- John G. Holt, Noel R. Krieg, editor, editor-in-chief (1984) Bergey's manual of systematic bacteriology volume2 page1809- 1825
- DOE JOINT GENOME INSTITUTE - US Department of Energy Office of Science http://genome.jgi-psf.org/finished_microbes/niteu/niteu.home.html
- DJW, Microbial of the Week 1999, Nirosomonas europae. http://web.umr.edu/~microbio/BIO221_1999/N_europaea.html
Edited by student of Rachel Larsen and Kit Pogliano
