Query: NC_008700:312099 Shewanella amazonensis SB2B, complete genome
Lineage: Shewanella amazonensis; Shewanella; Shewanellaceae; Alteromonadales; Proteobacteria; Bacteria
General Information: Isolated from shallow marine deposits (coastal shelf mud) of the Amazon River delta off of the coast of Brazil. Iron-reducing bacterium. This genus includes species that inhabit a wide range of environments and are capable of utilizing a wide variety of electron acceptors during anaerobic respiration including some insoluble metal oxides while using very few carbon sources such as lactate or acetate. This group of organisms have been studied extensively for their electron transport systems. Shewanella amazonensis is capable of anaerobically reducing iron, manganese, and sulfur compounds and may be important to the cycling of these compounds in the environment.
Subject: NC_004545:15650 Buchnera aphidicola str. Bp (Baizongia pistaciae), complete genome
Lineage: Buchnera aphidicola; Buchnera; Enterobacteriaceae; Enterobacteriales; Proteobacteria; Bacteria
General Information: This organism is found in the aphid Baizongia pistaciae. Aphid endosymbiont. 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.