Query: NC_012438:1600534 Sulfurihydrogenibium azorense Az-Fu1 chromosome, complete genome
Lineage: Sulfurihydrogenibium azorense; Sulfurihydrogenibium; Hydrogenothermaceae; Aquificales; Aquificae; Bacteria
General Information: This strain was isolated from a terrestrial hot spring in the Azores, where it was living at temperatures between 65 degrees C and 70 degrees C. Hydrogen-oxidizing thermophile. Sulfurihydrogenibium azorense is a thermophilic bacterium that is able to use hydrogen and sulfur compounds as electron donors. This organism is also able to use ferric iron and arsenate as electron acceptors. This is the first pure culture terrestrial member of the Aquificales group, isolated by dilution-to-extinction methods.
Subject: NC_002528:31191 Buchnera aphidicola str. APS (Acyrthosiphon pisum), complete
Lineage: Buchnera aphidicola; Buchnera; Enterobacteriaceae; Enterobacteriales; Proteobacteria; Bacteria
General Information: This strain is found in the pea aphid, Acyrthosiphon pisum.Aphid endosymbiont. Almost all aphids contain maternally transmitted bacteriocyte cells, which themselves contain bacteria called Buchnera. The aphids live on a restricted diet (plant sap), rich in carbohydrates, but poor in nitrogenous or other essential compounds. It is believed that the Buchnera provide the essential nutrients the host lacks. Besides a nutritional co-dependence, due to a co-existence of millions of years, Buchnera have lost the ability to produce cell surface components such as lipopolysaccharides. This makes for an obligate endosymbiont relationship between host and Buchnera. Buchnera are prokaryotic cells which belong to the gamma-Proteobacteria, closely related to the Enterobacteriaceae family. Phylogenetic studies using 16S rRNA indicate that the symbiotic relationship was established around 200-250 million years ago. Since Buchnera are closely related to Escherichia coli and Haemophilus influenzae, comparative genomic studies can shed light on the evolutionary mechanisms of intracellular endosymbiosis as well as the different underlying molecular basis between organisms with parasitic behavior and symbionts.