Nitrobacter
Encyclopedia
Nitrobacter is genus of mostly rod-shaped, gram-negative
, and chemoautotrophic bacteria.
Nitrobacter plays an important role in the nitrogen cycle
by oxidizing nitrite
into nitrate
in soil. Unlike plants, where electron transfer in photosynthesis
provides the energy for carbon fixation, Nitrobacter use energy from the oxidation of nitrite
ions, NO2-, into nitrate
ions, NO3- to fulfill their carbon requirements.
Nitrobacter have an optimum pH
between 7.3 and 7.5, and will die in temperatures exceeding 120°F (49°C) or below 32°F (0°C).
Some sources regard Nitrobacteraceae
to be the family of the genus Nitrobacter.
Species in the genus Nitrobacter include Nitrobacter winogradskyi, Nirobacter hamburgensis, Nitrobacter vulgaris and Nitrobacter alkalicus.
According to Grundmann, Nitrobacter seem to grow optimally at 38°C and at a pH of 7.9, but Holt states that Nitrobacter grow optimally at 28°C and grows within a pH range of 5.8 -8.5 and has an pH optima between 7.6 and 7.8. Nitrobacter belongs to the α-subclass of the Proteobacteria.
Nitrobacter may either be rod shaped, pear-shaped or pleomorphic. Cells normally reproduce by budding (Holt, 1993). Carboxysomes which aid carbon fixation are found in lithoautotrophically and mixotrophically grown cells. Additional energy conserving inclusions are PHB granules and polyphosphates. When both nitrite and organic substances are present, cells can exhibit biphasic growth, first the nitrite is used and after a lag phase, organic matter is oxidized. Chemoorganotrophic growth is slow and unbalanced thus more poly-β- hydroxybutyrate granules are seen that distort the shape and size of the cells.
Nitrobacter play an essential role in aquaponics
. Nitrosomonas
bacteria first convert ammonia into nitrites. Nitrobacter convert the nitrites into nitrates, which are readily absorbed by the plants.
Gram-negative
Gram-negative bacteria are bacteria that do not retain crystal violet dye in the Gram staining protocol. In a Gram stain test, a counterstain is added after the crystal violet, coloring all Gram-negative bacteria with a red or pink color...
, and chemoautotrophic bacteria.
Nitrobacter plays an important role in the nitrogen cycle
Nitrogen cycle
The nitrogen cycle is the process by which nitrogen is converted between its various chemical forms. This transformation can be carried out by both biological and non-biological processes. Important processes in the nitrogen cycle include fixation, mineralization, nitrification, and denitrification...
by oxidizing nitrite
Nitrite
The nitrite ion has the chemical formula NO2−. The anion is symmetric with equal N-O bond lengths and a O-N-O bond angle of ca. 120°. On protonation the unstable weak acid nitrous acid is produced. Nitrite can be oxidised or reduced, with product somewhat dependent on the oxidizing/reducing agent...
into nitrate
Nitrate
The nitrate ion is a polyatomic ion with the molecular formula NO and a molecular mass of 62.0049 g/mol. It 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...
in soil. Unlike plants, where electron transfer in photosynthesis
Photosynthesis
Photosynthesis is a chemical process that converts carbon dioxide into organic compounds, especially sugars, using the energy from sunlight. Photosynthesis occurs in plants, algae, and many species of bacteria, but not in archaea. Photosynthetic organisms are called photoautotrophs, since they can...
provides the energy for carbon fixation, Nitrobacter use energy from the oxidation of nitrite
Nitrite
The nitrite ion has the chemical formula NO2−. The anion is symmetric with equal N-O bond lengths and a O-N-O bond angle of ca. 120°. On protonation the unstable weak acid nitrous acid is produced. Nitrite can be oxidised or reduced, with product somewhat dependent on the oxidizing/reducing agent...
ions, NO2-, into nitrate
Nitrate
The nitrate ion is a polyatomic ion with the molecular formula NO and a molecular mass of 62.0049 g/mol. It 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...
ions, NO3- to fulfill their carbon requirements.
Nitrobacter have an optimum pH
PH
In chemistry, pH is a measure of the acidity or basicity of an aqueous solution. Pure water is said to be neutral, with a pH close to 7.0 at . Solutions with a pH less than 7 are said to be acidic and solutions with a pH greater than 7 are basic or alkaline...
between 7.3 and 7.5, and will die in temperatures exceeding 120°F (49°C) or below 32°F (0°C).
Some sources regard Nitrobacteraceae
Nitrobacteraceae
Nitrobacteraceae is a family of Alphaproteobacteria. They are gram-negative and aerobic.The bacteria of this family derive their energy from oxidizing ammonia to nitrite, or by oxidizing nitrite to nitrate.They are commonly found in freshwater and soil....
to be the family of the genus Nitrobacter.
Species in the genus Nitrobacter include Nitrobacter winogradskyi, Nirobacter hamburgensis, Nitrobacter vulgaris and Nitrobacter alkalicus.
According to Grundmann, Nitrobacter seem to grow optimally at 38°C and at a pH of 7.9, but Holt states that Nitrobacter grow optimally at 28°C and grows within a pH range of 5.8 -8.5 and has an pH optima between 7.6 and 7.8. Nitrobacter belongs to the α-subclass of the Proteobacteria.
Nitrobacter may either be rod shaped, pear-shaped or pleomorphic. Cells normally reproduce by budding (Holt, 1993). Carboxysomes which aid carbon fixation are found in lithoautotrophically and mixotrophically grown cells. Additional energy conserving inclusions are PHB granules and polyphosphates. When both nitrite and organic substances are present, cells can exhibit biphasic growth, first the nitrite is used and after a lag phase, organic matter is oxidized. Chemoorganotrophic growth is slow and unbalanced thus more poly-β- hydroxybutyrate granules are seen that distort the shape and size of the cells.
Nitrobacter play an essential role in aquaponics
Aquaponics
Aquaponics is a sustainable food production system that combines a traditional aquaculture with hydroponics in a symbiotic environment. In the aquaculture, effluents accumulate in the water, increasing toxicity for the fish...
. Nitrosomonas
Nitrosomonas
Nitrosomonas is a genus comprising rod shaped chemoautotrophic bacteria.This rare bacteria oxidizes ammonia into nitrite as a metabolic process. Nitrosomonas are useful in treatment of industrial and sewage waste and in the process of bioremediation. They are important in the nitrogen cycle by...
bacteria first convert ammonia into nitrites. Nitrobacter convert the nitrites into nitrates, which are readily absorbed by the plants.