Pre_GI: SWBIT SVG BLASTN

Query: NC_017254:545236 Buchnera aphidicola str. JF98 (Acyrthosiphon pisum) chromosome,

Lineage: Buchnera aphidicola; Buchnera; Enterobacteriaceae; Enterobacteriales; Proteobacteria; Bacteria

General Information: 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.

Subject: NC_007799:968499 Ehrlichia chaffeensis str. Arkansas, complete genome

Lineage: Ehrlichia chaffeensis; Ehrlichia; Anaplasmataceae; Rickettsiales; Proteobacteria; Bacteria

General Information: This strain is the first isolate of Ehrlichia chaffeensis, which was obtained from a patient on an army base in Arkansas, USA in 1990. Causes disease in humans. This organism is an obligate intracellular pathogen that exists within vacuoles in the cytoplasm of monocytes or granulocytes. Transferred during an insect (tick) bite, it can cause disease in humans (human monocytic ehrlichiosis) and can reside in several other animals and is a problem in immunocompromised patients. The bacterium inhibits phagosome-lysozome fusion as well as programmed cell death (apoptosis) of the host cell, similar to what is observed with Anaplasma phagocytophilum.