Query: NC_009883:140890 Rickettsia bellii OSU 85-389, complete genome
Lineage: Rickettsia bellii; Rickettsia; Rickettsiaceae; Rickettsiales; Proteobacteria; Bacteria
General Information: Transmitted via American ticks. This organism represents the third group of Rickettsial species and is separate from the spotted fever group and the typhus group. This organism is transovarially transmitted in American ticks and shows the largest range of host organisms including Dermacentor and Amblyomma.
Subject: NC_006142:57571 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.