Query: NC_017062:244330 Rickettsia typhi str. B9991CWPP chromosome, 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. This organism causes murine typhus and is an obligate intracellular pathogen that infects both the flea vector and hosts such as human, rat, and mouse. R. prowazekii, and genomic comparisons demonstrate colinearity and similarity to the genome of that organism except for two independent inversions near the origin and terminus. In the flea vector, the bacterium penetrates the gut epithelial barrier and is found in the feces which become infective.
Subject: NC_011883:1478173 Desulfovibrio desulfuricans subsp. desulfuricans str. ATCC 27774,
Lineage: Desulfovibrio desulfuricans; Desulfovibrio; Desulfovibrionaceae; Desulfovibrionales; Proteobacteria; Bacteria
General Information: Desulfovibrio desulfuricans subsp. desulfuricans str. ATCC 27774 was isolated from the rumen of a sheep. D. desulfuricans reduces sulfate to sulfide found in soil, freshwater, saltwater and the intestinal tract of animals. This organism grows anaerobically and utilizes a wide variety of electron acceptors, including sulfate, sulfur, nitrate, and nitrite, as well as others. The nitrate reduction pathway is not expressed while sulfate is available. Alternatively, the sulfate reduction pathway is constitutively expressed when the cells are growing with nitrate reduction. A number of toxic metals are reduced, including uranium (VI), chromium (VI) and iron (III), making this organism of interest as bioremediator. Metal corrosion, a problem that is partly the result of the collective activity of this bacterium, results in billions of dollars in losses each year to the petroleum industry. This organism is responsible for the production of poisonous hydrogen sulfide gas in marine sediments and in terrestrial environments such as drilling sites for petroleum products.