Query: NC_008209:695269 Roseobacter denitrificans OCh 114, complete genome
Lineage: Roseobacter denitrificans; Roseobacter; Rhodobacteraceae; Rhodobacterales; Proteobacteria; Bacteria
General Information: The aerobic phototrophic bacteria are ubiquitous as plant symbionts, free-living in lakes and ocean surface waters, soils and even near deep sea hydrothermal vents. Marine bacterium capable of aerobic anoxygenic photosynthesis. This bacterium was first isolated from a marine sediment collected on the coast of Australia. This organism's PufC photosynthetic protein has been studied as a classical tetraheme cytochrome, as it has all four possible heme-binding motifs.
Subject: NC_006397:1 Haloarcula marismortui ATCC 43049 chromosome II, complete sequence
Lineage: Haloarcula marismortui; Haloarcula; Halobacteriaceae; Halobacteriales; Euryarchaeota; Archaea
General Information: This organism was isolated from the Dead Sea and will provide information on the proteins necessary for adaptation to a high salt environment. Halophilic archaeon. Halobacterial species are obligately halophilic microorganisms that have adapted to optimal growth under conditions of extremely high salinity 10 times that of sea water. They contain a correspondingly high concentration of salts internally and exhibit a variety of unusual and unique molecular characteristics. Since their discovery, extreme halophiles have been studied extensively by chemists, biochemists, microbiologists, and molecular biologists to define both molecular diversity and universal features of life. A notable list of early research milestones on halophiles includes the discovery of a cell envelope composed of an S-layer glycoprotein, archaeol ether lipids and purple membrane, and metabolic and biosynthetic processes operating at saturating salinities. These early discoveries established the value of investigations directed at extremophiles and set the stage for pioneering phylogenetic studies leading to the three-domain view of life and classification of Halobacterium as a member of the archaeal domain. This organism is also know as "Halobacterium of the Dead Sea". Growth occurs in 1.7-5.1 M NaCl with optimum salt concentration of 3.4-3.9 M NaCl. The cytosol of this organism is a supersaturated salt solution in which proteins are soluble and active. This halophile is chemoorganotrophic and able to use a wide variety of compounds as sole carbon and energy sources.