Pre_GI: SWBIT SVG BLASTP

Query: NC_017378:1175639 Helicobacter pylori Puno120 chromosome, complete genome

Lineage: Helicobacter pylori; Helicobacter; Helicobacteraceae; Campylobacterales; Proteobacteria; Bacteria

General Information: This genus consists of organisms that colonize the mucosal layer of the gastrointestinal tract or are found enterohepatically (in the liver). It was only recently discovered (1983) by two Australians (Warren and Marshall) that this organism was associated with peptic ulcers. It is one of the most common chronic infectious organisms, and is found in half the world's population. This organism attacks the gastric epithilial surface, resulting in chronic gastritis, and can cause more severe diseases including those that lead to gastric carcinomas and lymphomas, peptic ulcers, and severe diarrhea. It is an extracellular pathogen that persists in the gastric environment, which has a very low pH, by production of the urease enzyme, which converts urea to ammonia and carbon dioxide, a process which can counteract the acidic environment by production of a base. The toxins include cytolethal distending toxin, vacuolating cytotoxin (VacA) that induces host epithelial cell apopoptosis (cell death), and the cytotoxin associated antigen (CagA) which results in alteration to the host cell signalling pathways. The CagA protein is translocated into host cells by a type IV secretion system encoded by the cag pathogenicity island.

Subject: NC_013418:397956 Blattabacterium sp. (Periplaneta americana) str. BPLAN, complete

Lineage: Blattabacterium; Blattabacterium; Blattabacteriaceae; Flavobacteriales; Bacteroidetes; Bacteria

General Information: This organism is the endosymbiont of the American cockroach, Periplaneta americana. It is a Gram-negative maternally inherited bacteria which lives in specialized cells in the host's abdominal fat body. Phylogenetic analyses for the Blattabacterium-cockroach symbiosis supports the hypothesis of co-evolution between symbionts and hosts dating back to more than 140 million years ago. Cockroaches are omnivorous insects, often subsisting on a nitrogen-poor diet, and Blattabacterium have been hypothesized to participate in uric acid degradation, nitrogen assimilation, and nutrient provisioning. Genome sequencing and metabolic reconstruction shows that Blattabacterium can recycle nitrogen from urea and ammonia, which are uric acid degradation products, into glutamate, using urease and glutamate dehydrogenase, and thus would be able to provide its host with some essential amino acids, vitamins and cofactors. The bacterium relies on asparagine and glutamine supplied by the host; it may be able to make proline from arginine via the urea cycle.