Query: NC_007517:687276 Geobacter metallireducens GS-15, complete genome
Lineage: Geobacter metallireducens; Geobacter; Geobacteraceae; Desulfuromonadales; Proteobacteria; Bacteria
General Information: First isolated from the Potomac river downstream of Washington, DC, USA in 1987. This organism actively moves towards metal attractants such as iron and manganese oxides, which are insoluble, and produces type IV pili for attachment to the insoluble substrates. Common metal-reducing bacterium. This organism, similar to what is observed in Geobacteria sulfurreducens, couples the oxidation of organic molecules to the reduction of iron by using insoluble Fe (III) as an electron acceptor under anaerobic conditions. This bacterium plays an imporant part of the nutrient cycling in aquatic environments. The cell can also use uranium and plutonium, therefore, this organism and may be important for the bioremediation of contaminated waste sites.
Subject: NC_003888:5042283 Streptomyces coelicolor A3(2), complete genome
Lineage: Streptomyces coelicolor; Streptomyces; Streptomycetaceae; Actinomycetales; Actinobacteria; Bacteria
General Information: Well-studied antiobiotic-producing bacterium. These bacteria are widely distributed in nature, especially in the soil. 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 bacterium is a soil-dwelling filamentous organism responsible for producing more than half of the known natural antibiotics. It is a well-studied species of Streptomyces and genetically is the best known representative.