Query: NC_017056:804416 Rickettsia prowazekii str. BuV67-CWPP chromosome, complete genome
Lineage: Rickettsia prowazekii; Rickettsia; Rickettsiaceae; Rickettsiales; Proteobacteria; Bacteria
General Information: This species is the causal agent of typhus. 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.
Subject: NC_008710:488815 Borrelia turicatae 91E135, complete genome
Lineage: Borrelia turicatae; Borrelia; Spirochaetaceae; Spirochaetales; Spirochaetes; Bacteria
General Information: This strain was isolated in the USA from the soft tick Ornithodoros turicatae. Borrelia turicatae is the causative agent of tick-borne relapsing fever in the southwestern USA. Ticks become infected with Borrelia while feeding on an infected mammal, usually a rodent or squirrel. Borrelia then multiplies rapidly, causing a generalized infection throughout the tick. While feeding, the tick passes the spirochete into a mammalian host through its infectious saliva. Relapsing fever is characterized by period of chills, fever, headache, and malaise, followed by an asymptomatic, followed by another episode of symptoms. The cycle of relapsing is due to changes in the surface proteins of Borrelia, which allow it to avoid detection and removal by the host immune system. This antigenic variation is the result of homologous recombination of silent proteins into an expressed locus, causing partial or complete replacement of one serotype with another. These plasmids carry genes involved in antigenic variation and pathogenicity.