Query: NC_008209:1097607 Roseobacter denitrificans OCh 114, complete genome
Lineage: Roseobacter denitrificans; Roseobacter; Rhodobacteraceae; Rhodobacterales; Proteobacteria; Bacteria
General Information: The aerobic phototrophic bacteria are ubiquitous as plant symbionts, free-living in lakes and ocean surface waters, soils and even near deep sea hydrothermal vents. Marine bacterium capable of aerobic anoxygenic photosynthesis. This bacterium was first isolated from a marine sediment collected on the coast of Australia. This organism's PufC photosynthetic protein has been studied as a classical tetraheme cytochrome, as it has all four possible heme-binding motifs.
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.