Query: NC_013714:2350749 Bifidobacterium dentium Bd1, complete genome Lineage: Bifidobacterium dentium; Bifidobacterium; Bifidobacteriaceae; Bifidobacteriales; Actinobacteria; Bacteria General Information: Common oral and gut bacterium. Representatives of this genus naturally colonize the human gastrointestinal tract (GIT) and are important for establishing and maintaining homeostasis of the intestinal ecosystem to allow for normal digestion. Their presence has been associated with beneficial health effects, such as prevention of diarrhea, amelioration of lactose intolerance, or immunomodulation. The stabilizing effect on GIT microflora is attributed to the capacity of bifidobacteria to produce bacteriocins, which are bacteriostatic agents with a broad spectrum of action, and to their pH-reducing activity. Most of the ~30 known species of bifidobacteria have been isolated from the mammalian GIT, and some from the vaginal and oral cavity. All are obligate anaerobes belonging to the Actinomycetales, branch of Gram-positive bacteria with high GC content that also includes Corynebacteria, Mycobacteria, and Streptomycetes. Bifidobacterium dentium species represents over forty strains which were isolated from human dental caries and human feces.
- Sequence; - BLASTP hit: hover for score (Low score = Light, High score = Dark); - hypothetical protein; - cds: hover for description
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.