Query: NC_009457:2095366 Vibrio cholerae O395 chromosome 2, complete sequence
Lineage: Vibrio cholerae; Vibrio; Vibrionaceae; Vibrionales; Proteobacteria; Bacteria
General Information: Aquatic organism that causes Cholera. This genus is abundant in marine or freshwater environments such as estuaries, brackish ponds, or coastal areas; regions that provide an important reservoir for the organism in between outbreaks of the disease. Vibrio can affect shellfish, finfish, and other marine animals and a number of species are pathogenic for humans. Vibrio cholerae can colonize the mucosal surface of the small intestines of humans where it will cause cholera, a severe and sudden onset diarrheal disease. One famous outbreak was traced to a contaminated well in London in 1854 by John Snow, and epidemics, which can occur with extreme rapidity, are often associated with conditions of poor sanitation. The disease has a high lethality if left untreated, and millions have died over the centuries. There have been seven major pandemics between 1817 and today. Six were attributed to the classical biotype, while the 7th, which started in 1961, is associated with the El Tor biotype.
Subject: NC_006368:3028286 Legionella pneumophila str. Paris, complete genome
Lineage: Legionella pneumophila; Legionella; Legionellaceae; Legionellales; Proteobacteria; Bacteria
General Information: This serogroup I strain is endemic in France. Causes Legionnaire's disease. This organism is a non-marine bacterium usually found growing inside other organisms such as protozoans in aquatic environments. They can also be found in soil, freshwater, and in biofilms. The first outbreak of Legionnaire's disease occurred in 1976 at an American Legion convention and the resulting pneumonia-like disease resulted in 34 deaths. The cause of the disease was traced to Legionella bacteria. Once the bacteria are brought into the lungs they make contact with alveolar macrophages and are internalized where they can cause severe respiratory distress. Internalization occurs through specialized vacuoles (replicative phagosomes) that allow the bacteria to grow and replicate prior to escape from the macrophage. Formation of the replicative phagosome, which requires reprogramming of the normal phagosome maturation pathway, requires a type IV secretion system called the Dot/Icm system. This type IV system is closely related to the conjugative system of plasmid ColIb-P9, and is involved in the secretion of numerous protein components that aid in formation of the replicative phagosome. Other virulence determinants include a set of multidrug transporters and other efflux pumps for toxic compounds that may allow the organism to persist in its habitat, a set of LPS phase variable genes that enhance immune evasion, and a type II secretion system for transport of hydrolases.