Query: NC_000868:196015 Pyrococcus abyssi GE5, complete genome
Lineage: Pyrococcus abyssi; Pyrococcus; Thermococcaceae; Thermococcales; Euryarchaeota; Archaea
General Information: This organism was isolated from an active chimney in the North Fiji Basin of the Pacific Ocean at a depth of 3500 meters. This organism is an obligate anaerobic, hyperthermophilic archaeon. Growth occurs at a temperature of 67-103 degrees C with optimal growth at 103 degrees C at 200 atmospheres of pressure. Increased hydrostatic pressure has been found to extend the upper growth temperature and stimulate growth.
Subject: NC_008513:343540 Buchnera aphidicola str. Cc (Cinara cedri), complete genome
Lineage: Buchnera aphidicola; Buchnera; Enterobacteriaceae; Enterobacteriales; Proteobacteria; Bacteria
General Information: This strain is found in the cedar aphid, Cinara cedri. 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.