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_004557:1 Clostridium tetani E88, complete genome
Lineage: Clostridium tetani; Clostridium; Clostridiaceae; Clostridiales; Firmicutes; Bacteria
General Information: This strain is a virulent nonsporulating variant of strain Massachusetts used in vaccine production. Causes tetanus. 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. Known opportunistic toxin-producing pathogens in animals and humans. Some species are capable of producing organic solvents (acetone, ethanol, etc,), molecular hydrogen and other useful compounds. This organism causes tetanus (lockjaw) in humans. At the tissue level, the bacterium then releases an exotoxin called tetanospasmin that causes certain nervous system irregularities by means of retrograde tramsmission through neurons to the brain. If nervous impulses cannot be checked by normal inhibitory mechanisms, it produces the generalized muscular spasms characteristic of tetanus.