Pre_GI: SWBIT SVG BLASTN

Query: NC_009699:490652 Clostridium botulinum F str. Langeland chromosome, complete genome

Lineage: Clostridium botulinum; Clostridium; Clostridiaceae; Clostridiales; Firmicutes; Bacteria

General Information: Clostridium botulinum F strain Langeland was identified in 1958 from home-prepared liver paste involved in an outbreak of foodborne botulism on the island of Langeland, in Denmark. Produces botulinum, one of the most potent toxins known. This genus comprises about 150 metabolically diverse species of anaerobes that are ubiquitous in virtually all anoxic habitats where organic compounds are present, including soils, aquatic sediments and the intestinal tracts of animals and humans. This shape is attributed to the presence of endospores that develop under conditions unfavorable for vegetative growth and distend single cells terminally or sub-terminally. Spores germinate under conditions favorable for vegetative growth, such as anaerobiosis and presence of organic substrates. It is believed that present day Mollicutes (Eubacteria) have evolved regressively (i.e., by genome reduction) from gram-positive clostridia-like ancestors with a low GC content in DNA. This organism produces one of the most potent and deadly neurotoxins known, a botulinum toxin that prevents the release of acetylcholine at the neuromuscular junction, thereby inhibiting muscle contraction and causing paralysis. In most cases the diseased person dies of asphyxiation as a result of paralysis of chest muscles involved in breathing. The spores are heat-resistant and can survive in inadequately heated, prepared, or processed foods. Spores germinate under favorable conditions (anaerobiosis and substrate-rich environment) and bacteria start propagating very rapidly, producing the toxin. Botulinum toxin, and C. botulinum cells, has been found in a wide variety of foods, including canned ones. Almost any food that has a high pH (above 4.6) can support growth of the bacterium.

Subject: NC_004337:3590323 Shigella flexneri 2a str. 301, complete genome

Lineage: Shigella flexneri; Shigella; Enterobacteriaceae; Enterobacteriales; Proteobacteria; Bacteria

General Information: This strain was isolated in 1984 from a patient in Beijing, China. It is similar to pathogenic Escherichia coli except for the more numerous insertion sequences and contains a virulence plasmid (pCP301). Causes enteric disease. Shigella This genus is named for the Japanese scientist (Shiga) who discovered them in the 1890s. They are closely related to the Escherichia group, and may be considered the same species. are human-specific pathogens that are transmitted via contaminated food and water and are the leading causes of endemic bacillary dysentery, and over 1 million deaths worldwide are attributed to them. The bacteria infect the epithelial lining of the colon, causing acute inflammation by entering the host cell cytoplasm and spreading intercellularly. are extremely virulent organisms that require very few cells in order to cause disease. Both the type III secretion system, which delivers effector molecules into the host cell, and some of the translocated effectors such as the invasion plasmid antigens (Ipas), are encoded on the plasmid. The bacterium produces a surface protein that localizes to one pole of the cell (IcsA) which binds to and promotes actin polymerization, resulting in movement of the bacterium through the cell cytoplasm, and eventually to neighboring cells, which results in inflammatory destruction of the mucosal lining. This organism, along with Shigella sonnei, is the major cause of shigellosis in industrialized countries and is responsible for endemic infections.