Query: NC_013199:811929 Lactobacillus rhamnosus Lc 705, complete genome
Lineage: Lactobacillus rhamnosus; Lactobacillus; Lactobacillaceae; Lactobacillales; Firmicutes; Bacteria
General Information: They are commonly found in the oral, vaginal, and intestinal regions of many animals. They are important industrial microbes that contribute to the production of cheese, yogurt, and other products such as fermented milks, all stemming from the production of lactic acid, which inhibits the growth of other organisms as well as lowering the pH of the food product. Industrial production requires the use of starter cultures, which are carefully cultivated, created, and maintained, which produce specific end products during fermentation that impart flavor to the final product, as well as contributing important metabolic reactions, such as the breakdown of milk proteins during cheese production. The end product of fermentation, lactic acid, is also being used as a starter molecule for complex organic molecule syntheses. Lactobacillus rhamnosus is used in the manufacture of cheese and other dairy products to aid ripening and enhance flavors. This organism has also been shown to stimulate the immune system and have antibacterial activity against intestinal pathogens, indicating that it may be useful as a probiotic.
Subject: NC_003366:2556457 Clostridium perfringens str. 13, complete genome
Lineage: Clostridium perfringens; Clostridium; Clostridiaceae; Clostridiales; Firmicutes; Bacteria
General Information: This strain is a type A isolate from the soil. It can establish gas gangrene in a murine experimental model. Causative agent of gas gangrene. 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. This organism is a causative agent of a wide spectrum of necrotic enterotoxicoses. It also causes such animal diseases as lamb dysentery, ovine enterotoxemia (struck), pulpy kidney disease in lambs and other enterotoxemias in lambs and calves. It is commonly found in the environment (soil, sewage) and in the animal and human gastrointestinal tract as a member of the normal microflora. It is a fast growing (generation time 8-10 min) anaerobic flesh-eater. Active fermentative growth is accompanied by profuse generation of molecular hydrogen and carbon dioxide. It is also oxygen tolerant which makes it an easy object to work with in laboratories. Known isolates belong to five distinct types (A, B, C, D, and E) that are distinguished based on the specific extracellular toxins they produce. Known isolates belong to five distinct types (A, B, C, D, and E) that are distinguished based on the specific extracellular toxins they produce. All types produce the alpha toxin (phospholipase C). Type A strains that cause gas gangrene produce alpha toxin, theta (hemolysin), kappa (collagenase), mu (hyaluronidase), nu (DNAse) and neuraminidase which are all the enzymatic factors aiding the bacterium in invading and destruction of the host tissues. Type C strains produce alpha toxin, beta toxin and prefringolysin enteritis. In addition to alpha toxin, Type B strains produce beta toxin, types B and D produce the pore forming epsilon toxin and type E strains produce iota toxin.