Query: NC_013009:721823 Neorickettsia risticii str. Illinois, complete genome
Lineage: Neorickettsia risticii; Neorickettsia; Anaplasmataceae; Rickettsiales; Proteobacteria; Bacteria
General Information: Neorickettsia risticii str. Illinois was isolated from horse blood in Maryland, USA. Neorickettsia risticii, formerly Ehrlichia risticii, is an obligate intracellular bacterium related to the Rickettsia. It can be transmitted from flukes that infest snails, fish or aquatic insects to horses by ingestion. This organism causes Potomac horse fever, also knows as equine monocytic ehrlichiosis, an acute diarrheal disease.
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.