Query: NC_010673:479552 Borrelia hermsii DAH, complete genome
Lineage: Borrelia hermsii; Borrelia; Spirochaetaceae; Spirochaetales; Spirochaetes; Bacteria
General Information: This strain was isolated from a case of relapsing fever in western Washington, USA. Borrelia hermsii is the causative agent of tick-borne relapsing fever in the western United States and Canada. Borrelia then multiplies rapidly, causing a generalized infection throughout the tick. While feeding, the tick passes the organism into a mammalian host through its infectious saliva. Relapsing fever is characterized by a period of chills, fever, headache, and malaise, an asymptomatic period, followed by another episode of symptoms. This 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.
Subject: NC_012563:3956500 Clostridium botulinum A2 str. Kyoto, complete genome
Lineage: Clostridium botulinum; Clostridium; Clostridiaceae; Clostridiales; Firmicutes; Bacteria
General Information: This strain was isolated from a case of infant botulism in Kyoto, Japan in 1978. 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. Honey is the most common vehicle for infection in infants. Food poisoning through C. botulinum is the most frequent type of infection caused by this bacterium. The wound botulism that occurs when C. botulinum infects an individual via an open wound is much rarer and is very similar to tetanus disease. There are several types of botulinum toxin known (type A through type F), all of them being neurotoxic polypeptides. The most common and widely distributed are strains and serovars of C. botulinum that produce type A toxin.