Bradyrhizobium japonicum
| Bradyrhizobium japonicum | ||||||||||||
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Bradyrhizobium japonicum |
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| Scientific name | ||||||||||||
| Bradyrhizobium japonicum | ||||||||||||
| ( Kirchner 1896) Jordan 1982 |
B. japonicum is a bacteria art from the family of Rhizobiales . As a nitrogen- fixing symbiont of the soybean ( Glycine max ), it is one of the most economically important bacteria.
features
Bradyrhizobium japonicum is a rod-shaped, gram-negative bacterium. Like other species of the genus Bradyrhizobium , the species grows slowly in culture and produces alkaline medium without a serum zone in Litmus milk. The species is distinguished from other species of the genus on the basis of serum tests and DNA sequence . Only this species and the closely related Bradyrhizobium elkani occur as symbionts of the soybean. The systematic position and the separation of the two species have not been conclusively clarified. A sequence of the genome of B. japonicum has been available since 2002 . The genome size is 9.1 million base pairs , the GC content is 64.1 percent.
symbiosis
Bradyrhizobium japonicum lives as a symbiote in the soybean root nodules . Lipochitin, which is only formed after contact with vegetable flavonoids , serves as a bacterial signal for the formation of nodules . The bacteria are endocytosed and live as bacteroids in a special organelle, the symbiosome . There they fix nitrogen to ammonium for the plant and receive nutrients in return.
In the root nodule, the bacteroids are supplied with oxygen by leghemoglobin for the energy-intensive nitrogen fixation . By binding the oxygen to the leghemoglobin, the oxygen-sensitive enzymes of nitrogen fixation also remain protected.
Since Bradyrhizobium japonicum does not occur naturally in Central European soils, seeds or arable land, or both, are "inoculated" with these bacteria before or during sowing.
swell
- Herman P. Spaink, Adam Kondorosi, Paul JJ Hooykaas: The Rhizobiaceae: Molecular Biology of Model Plant-associated Bacteria . Springer, 1998, ISBN 978-0-7923-5180-1 .
- ↑ Takakazu Kaneko, Yasukazu Nakamura, Shusei Sato, Kiwamu Minamisawa, Toshiki Uchiumi, Shigemi Sasamoto, Akiko Watanabe, Kumi Idesawa, Mayumi Iriguchi, Kumiko Kawashima, Mitsuyo Kohara, Midori Matsumoto, Satosuko Shimpo, Manaehiu Yamoka, Midori Matsumoto Tabata: Complete Genomic Sequence of Nitrogen-fixing Symbiotic Bacterium Bradyrhizobium japonicum USDA110 . In: DNA Research . tape 9 , 2002, p. 189-197 (English, oxfordjournals.org ).
- ↑ Vaccination - Soy Conveyor Ring. Accessed April 12, 2019 (German).