Query: NC_010337:2339056 Heliobacterium modesticaldum Ice1, complete genome
Lineage: Heliobacterium modesticaldum; Heliobacterium; Heliobacteriaceae; Clostridiales; Firmicutes; Bacteria
General Information: Heliobacterium modesticaldum strain Ice1, the type strain of this species, was isolated from Icelandic hot spring volcanic soils. It grows optimally above 50 degrees Celsius, grows best photoheterotrophically, but can grow in the dark chemotrophically on pyruvate. Phototrophic thermophile. This organism is an anoxygenic phototroph isolated from hot spring microbial mats and volcanic soil. Cell wall structure, the ability to form endospores, and 16S ribosomal RNA analysis place Heliobacterium modesticaldum in a family of phototrophic bacteria related to the Clostridia. Heliobacterium modesticaldum is able to fix nitrogen and may contribute significantly to the nitrogen availability in microbial mats.
Subject: NC_003366:64908 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.