Pre_GI: SWBIT SVG BLASTN

Query: NC_009089:3142976 Clostridium difficile 630, complete genome

Lineage: Peptoclostridium difficile; Peptoclostridium; Peptostreptococcaceae; Clostridiales; Firmicutes; Bacteria

General Information: This strain is the epidemic type X variant that has been extensively studied in research and clinical laboratories. It produces both toxin A, and B. Causative agent of pseudomembranous colitis. This genus comprises about 150 metabolically diverse species of anaerobes that are ubiquitous in virtually all anoxic habitats where organic compounds are present, including soils, aquatic sediments and the intestinal tracts of animals and humans. This shape is attributed to the presence of endospores that develop under conditions unfavorable for vegetative growth and distend single cells terminally or sub-terminally. Spores germinate under conditions favorable for vegetative growth, such as anaerobiosis and presence of organic substrates. It is believed that present day Mollicutes (Eubacteria) have evolved regressively (i.e., by genome reduction) from gram-positive clostridia-like ancestors with a low GC content in DNA. Some species are capable of producing organic solvents (acetone, ethanol, etc,), molecular hydrogen and other useful compounds. This species is now recognized as the major causative agent of pseudomembranous colitis (inflammation of the colon) and diarrhea that may occur following antibiotic treatment. This bacterium causes a wide spectrum of disease, ranging from mild, self-limiting diarrhea to serious diarrhea and, in some cases, complications such as pseudomembrane formation, toxic megacolon (dilation of the colon) and peritonitis, which often lead to lethality among patients. The bacteria produce high molecular mass polypeptide cytotoxins, A and B. Some strains produce only one of the toxins, others produce both. Toxin A causes inflammatory reaction involving hypersecretion of fluid and hemorrhagic necrosis through triggering cytokine release by neutrophils. Alteration of intestinal microbial balance with antibiotic therapy and increased exposure to the bacterium in a hospital setting allows C. difficile to colonize susceptible individuals. Moreover, it has been shown that subinhibitory concentrations of antibiotics promote increased toxin production by C. difficile.

Subject: NC_008525:270310 Pediococcus pentosaceus ATCC 25745, complete genome

Lineage: Pediococcus pentosaceus; Pediococcus; Lactobacillaceae; Lactobacillales; Firmicutes; Bacteria

General Information: Use in fermentation of food products. A distinctive characteristic of pediococci is their ability to form tetrads via cell division in two perpendicular directions in a single plane. Like other lactic acid bacteria, species of Pediococcus are acid tolerant, cannot synthesize porphyrins, and possess a strictly fermentative (homofermentative) facultatively anaerobic metabolism with lactic acid as the major metabolic end product. They also occur in such food products as cured meat, raw sausages, and marinated fish, and are are used for biotechnological processing and preservation of foods. This bacterium can be isolated from a variety of plant materials and bacterial-ripened cheeses. This organism is used as an acid producing starter culture in the fermentation of some sausages, cucumbers, green beans, soy milk, and silage. Some strains have been reported to contain several (3-5) resident plasmids that render the bacterium capable of fermenting some sugars (raffinose, melibiose, and sucrose), as well as producing bacteriocins.