Query: NC_017066:243913 Rickettsia typhi str. TH1527 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_014802:716699 Campylobacter jejuni subsp. jejuni ICDCCJ07001 chromosome, complete
Lineage: Campylobacter jejuni; Campylobacter; Campylobacteraceae; Campylobacterales; Proteobacteria; Bacteria
General Information: Gram-negative, microaerophilic, flagellate, spiral bacterium, Campylobacter species are the leading cause of food-borne gastroenteritis in developed countries. Infection with C. jejuni is the most frequent antecedent to a form of neuromuscular paralysis known as Guillain-Barre syndrome (GBS). Strain ICDCCJ07001 was isolated following a GBS outbreak in Shuangyang, a town in northern China in 2007, from a severely affected 15 year-old girl GBS patient who had been on a ventilator for 180 days. Her clinical symptoms were motor axonal neuropathy. This organism is the leading cause of bacterial food poisoning (campylobacteriosis) in the world, and is more prevalent than Salmonella enteritis (salmonellosis). Found throughout nature, it can colonize the intestines of both mammals and birds, and transmission to humans occurs via contaminated food products. This organism can invade the epithelial layer by first attaching to epithelial cells, then penetrating through them. Systemic infections can also occur causing more severe illnesses.