Pre_GI: SWBIT SVG BLASTN

Query: NC_017379:1035464 Helicobacter pylori Puno135 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_008767:1888950 Neisseria meningitidis FAM18, complete genome

Lineage: Neisseria meningitidis; Neisseria; Neisseriaceae; Neisseriales; Proteobacteria; Bacteria

General Information: Isolated from a patient with meningococcal septicemia. Causes septicemia and meningitis. The second of two pathogenic Neisseria, this organism causes septicemia and is the leading cause of life-threatening meningitis (inflammation of the meninges, the membrane surrounding the brain and spinal cord) in children. This organism typically residies in the nasopharynx cavity but can invade the respiratory epthelial barrier, cross into the bloodstream and the blood brain barrier, and cause inflammation of the meninges. Pathogenicity factors include the surface proteins (porins and opacity proteins), and the type IV pilus (which is also found in Neisseria gonorrhoeae). Pathogenicity factors include the surface proteins (porins and opacity proteins), and the type IV pilus (which is also found in Neisseria gonorrhoeae). This organism, like Neisseria gonorrhoeae, is naturally competent, and protein complexes at the cell surface recognize the uptake signal sequence in extracellular DNA, an 8mer that is found at high frequency in Neisseria chromosomal DNA.