Query: NC_008686:1960034 Paracoccus denitrificans PD1222 chromosome 1, complete sequence
Lineage: Paracoccus denitrificans; Paracoccus; Rhodobacteraceae; Rhodobacterales; Proteobacteria; Bacteria
General Information: This organism is commonly found in soil and sewage sludge. This organism is able to survive in both aerobic and anaerobic environments due to its ability to use both oxygen and nitrogenous oxides making it a popular model organism for the study of electron transfer and and energy conservation.
Subject: NC_008380:58232 Rhizobium leguminosarum bv. viciae 3841, complete genome
Lineage: Rhizobium leguminosarum; Rhizobium; Rhizobiaceae; Rhizobiales; Proteobacteria; Bacteria
General Information: This biovar nodulates legumes in the Tribe Viciae (Vicia, Pisum, Lathyrus, Lens). This strain is a spontaneous streptomycin-resistant mutant of strain 300. Nitrogen-fixing plant symbiont. This organism, like other Rhizobia, establishes a symbiotic relationship with a legume plant, providing nitrogen in exchange for a protected environment. The legume roots secrete flavonoids and isoflavonoids which the bacteria recognize and use to turn on genes involved in root nodulation. Many of the root nodulation genes are involved in synthesis and secretion of a nodule inducing signal, a lipochito-oligosaccharide molecule, which the plant recognizes, triggering nodule formation. The bacterium is endocytosed and exists inside a membrane bound organelle, the symbiosome, and fixes nitrogen for the plant cell while the host cell provides carbon compounds for the bacterium to grow on. The nitrogen fixation is important as it obviates the need for expensive and environmentally damaging fertilizer use.