Bradyrhizobium japonicum | |
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Bradyrhizobium japonicum strain USDA 110 on an agar plate. | |
Scientific classification | |
Kingdom: | Bacteria |
Phylum: | Proteobacteria |
Class: | Alphaproteobacteria |
Order: | Rhizobiales |
Family: | Bradyrhizobiaceae |
Genus: | Bradyrhizobium |
Species: | B. japonicum |
Binomial name | |
Bradyrhizobium japonicum (Kirchner 1896) Jordan, 1982 |
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Synonyms | |
Rhizobium japonicum Buchanan 1926 |
Bradyrhizobium japonicum is a species of legume-root nodulating, microsymbiotic nitrogen-fixing bacterium species. B. japonicum is identified as a DNA homology group (group II)[2].
B. japonicum is able to degrade catechin with formation of phloroglucinol carboxylic acid, further decarboxylated to phloroglucinol, which is dehydroxylated to resorcinol and hydroxyquinol.
B. japonicum possess the nosRZDFYLX gene, which aides in denitrification and has two catalytic subunits - Cu-a and Cu-z (with several histidine residues). It manages an expression cascade that can sense oxygen gradients, termed 'FixJ-FixK2-FixK1.' FixJ positively regulates FixK2, which activates nitrogen respiration genes as well as FixK1. FixK1 mutants are unable to respire from nitrogen due to a defective catatylic copper subunit (Cu-z) in nosRZDFYLX.[3].