Query: NC_009881:166500 Rickettsia akari str. Hartford, complete genome
Lineage: Rickettsia akari; Rickettsia; Rickettsiaceae; Rickettsiales; Proteobacteria; Bacteria
General Information: This strain was isolated from mites in Hartford. Causative agent of Rickettsialpox. Members of this genus, like other Rickettsial organisms such as Neorickettsia and Anaplasma, are obligate intracellular pathogens. In both groups, the bacteria are transmitted via an insect, usually a tick, to a host organism 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. Rickettsia akari causes a mild disease, Rickettsialpox, which is an acute fever-inducing illness transmitted by a hematophagous mite that infects the common house mouse and bites humans. Infection by this organism may be confused with anthrax due to the black eschar. This bacterium is a member of the spotted fever group of Rickettsiales and is endemic to New York, USA, but is also found in other cities in the USA, Russia, South Korea, and South Africa.
Subject: NC_003155:5957657 Streptomyces avermitilis MA-4680, complete genome
Lineage: Streptomyces avermitilis; Streptomyces; Streptomycetaceae; Actinomycetales; Actinobacteria; Bacteria
General Information: This strain (ATCC 31267) was isolated and characterized in 1978 by R. Burg and colleagues from a soil sample collected in Shizuoka Prefecture, Japan. Antibiotic-producing bacterium. The characteristic earthy smell of freshly plowed soil is actually attributed to the aromatic terpenoid geosmin produced by species of Streptomyces. There are currently 364 known species of this genus, many of which are the most important industrial producers of antibiotics and other secondary metabolites of antibacterial, antifungal, antiviral, and antitumor nature, as well as immunosuppressants, antihypercholesterolemics, etc. Streptomycetes are crucial in the soil environment because their diverse metabolism allows them to degrade the insoluble remains of other organisms, including recalcitrant compounds such as lignocelluloses and chitin. Streptomycetes produce both substrate and aerial mycelium. The latter shows characteristic modes of branching, and in the course of the streptomycete complex life cycle, these hyphae are partly transformed into chains of spores, which are often called conidia or arthrospores. An important feature in Streptomyces is the presence of type-I peptidoglycan in the cell walls that contains characteristic interpeptide glycine bridges. Another remarkable trait of streptomycetes is that they contain very large (~8 million base pairs which is about twice the size of most bacterial genomes) linear chromosomes with distinct telomeres. These rearrangements consist of the deletion of several hundred kilobases, often associated with the amplification of an adjacent sequence, and lead to metabolic diversity within the Streptomyces group. Sequencing of several strains of Streptomyces is aimed partly on understanding the mechanisms involved in these diversification processes. This organism is a well known producer of the anti-parasitic agent avermectin which is widely used to rid livestock of worm and insect infestations and to protect large numbers of people from river blindness in sub-Saharan Africa.