Query: NC_007761:3962474 Rhizobium etli CFN 42, complete genome
Lineage: Rhizobium etli; Rhizobium; Rhizobiaceae; Rhizobiales; Proteobacteria; Bacteria
General Information: It is a nitrogen-fixing symbiotic bacteria that interacts with the root of the common bean plant Phaseolus vulgaris. P. etli and its relation to other nitrogen/fixing symbionts has been well studied. The genomic sequence will provide information on the process of symbiosis, on the genetic systems that allow the survival and adaptations of this bacteria to the soil, and on the evolutionary relationship and the symbiosis origin of this organism.
Subject: NC_006142:33268 Rickettsia typhi str. Wilmington, complete genome
Lineage: Rickettsia typhi; Rickettsia; Rickettsiaceae; Rickettsiales; Proteobacteria; Bacteria
General Information: This genus, like other Rickettsial organisms such as Neorickettsia and Anaplasma, is composed of obligate intracellular pathogens. The latter is composed of two organisms, Rickettsia prowazekii and Rickettsia typhi. The bacteria are transmitted via an insect, usually a tick, to a host organism, in this case humans, where they target endothelial cells and sometimes macrophages. They attach via an adhesin, rickettsial outer membrane protein A, and are internalized where they persist as cytoplasmically free organisms. Transovarial transmission (from mother to offspring) occurs in the invertebrate host. Rickettsia typhi causes murine typhus and is an obligate intracellular pathogen that infects both the flea vector and hosts such as human, rat, and mouse. In the flea vector, the bacterium penetrates the gut epithelial barrier and is found in the feces which become infective.