Bifidobacterium dentium | |
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Scientific classification | |
Domain: | Bacteria |
Phylum: | Actinomycetota |
Class: | Actinomycetia |
Order: | Bifidobacteriales |
Family: | Bifidobacteriaceae |
Genus: | Bifidobacterium |
Species: | B. dentium |
Binomial name | |
Bifidobacterium dentium Scardovi and Crociani 1974 (Approved Lists 1980) [1] | |
Bifidobacterium dentium is a species of bacteria in the genus Bifidobacterium , branched anaerobic bacteria from the Bifidobacteriaceae family.
B. dentium is a source of anaerobic infections, and is also tracked in polluted water to trace the source of fecal contamination. Scientists have shown that B. dentium can cause tooth decay in humans. Due to its high tolerance of the acidic environments reached by the human mouth (pH 4.5), B. dentium can sustain growth in the oral cavities, cause harm to the teeth, and break down sugars. [2]
B. dentium has been identified by researchers at Baylor College of Medicine and Texas Children's Hospital as producing a neurotransmitter that may play a role in preventing or treating inflammatory bowel diseases such as Crohn's disease. [3]
B. dentium is also a member of the gut flora. It colonizes the intestinal mucus layer, where it has been found to produce acetate. In addition, B. dentium produces the neurotransmitter GABA and other products which regulate intestinal goblet cells. In addition, B. dentium may be involved in the development of mucin. [4]
The human microbiome is the aggregate of all microbiota that reside on or within human tissues and biofluids along with the corresponding anatomical sites in which they reside, including the gastrointestinal tract, skin, mammary glands, seminal fluid, uterus, ovarian follicles, lung, saliva, oral mucosa, conjunctiva, and the biliary tract. Types of human microbiota include bacteria, archaea, fungi, protists, and viruses. Though micro-animals can also live on the human body, they are typically excluded from this definition. In the context of genomics, the term human microbiome is sometimes used to refer to the collective genomes of resident microorganisms; however, the term human metagenome has the same meaning.
Fusobacterium is a genus of obligate anaerobic, Gram-negative, non-sporeforming bacteria belonging to Gracilicutes. Individual cells are slender, rod-shaped bacilli with pointed ends. Fusobacterium was discovered in 1900 by Courmont and Cade and is common in the flora of humans.
Mucus is a slippery aqueous secretion produced by, and covering, mucous membranes. It is typically produced from cells found in mucous glands, although it may also originate from mixed glands, which contain both serous and mucous cells. It is a viscous colloid containing inorganic salts, antimicrobial enzymes, immunoglobulins, and glycoproteins such as lactoferrin and mucins, which are produced by goblet cells in the mucous membranes and submucosal glands. Mucus serves to protect epithelial cells in the linings of the respiratory, digestive, and urogenital systems, and structures in the visual and auditory systems from pathogenic fungi, bacteria and viruses. Most of the mucus in the body is produced in the gastrointestinal tract.
Lactobacillus acidophilus is a rod-shaped, Gram-positive, homofermentative, anaerobic microbe first isolated from infant feces in the year 1900. The species is commonly found in humans, specifically the gastrointestinal tract and oral cavity as well as some speciality fermented foods such as fermented milk or yogurt, though it is not the most common species for this. The species most readily grows at low pH levels, and has an optimum growth temperature of 37 °C. Certain strains of L. acidophilus show strong probiotic effects, and are commercially used in dairy production. The genome of L. acidophilus has been sequenced.
Goblet cells are simple columnar epithelial cells that secrete gel-forming mucins, like mucin 2 in the lower gastrointestinal tract, and mucin 5AC in the respiratory tract. The goblet cells mainly use the merocrine method of secretion, secreting vesicles into a duct, but may use apocrine methods, budding off their secretions, when under stress. The term goblet refers to the cell's goblet-like shape. The apical portion is shaped like a cup, as it is distended by abundant mucus laden granules; its basal portion lacks these granules and is shaped like a stem.
Gut microbiota, gut microbiome, or gut flora are the microorganisms, including bacteria, archaea, fungi, and viruses, that live in the digestive tracts of animals. The gastrointestinal metagenome is the aggregate of all the genomes of the gut microbiota. The gut is the main location of the human microbiome. The gut microbiota has broad impacts, including effects on colonization, resistance to pathogens, maintaining the intestinal epithelium, metabolizing dietary and pharmaceutical compounds, controlling immune function, and even behavior through the gut–brain axis.
Bacteroides is a genus of Gram-negative, obligate anaerobic bacteria. Bacteroides species are non endospore-forming bacilli, and may be either motile or nonmotile, depending on the species. The DNA base composition is 40–48% GC. Unusual in bacterial organisms, Bacteroides membranes contain sphingolipids. They also contain meso-diaminopimelic acid in their peptidoglycan layer.
Fusobacterium nucleatum is a Gram-negative, anaerobic bacterium, commensal to the human oral cavity, that plays a role in periodontal disease. This organism is commonly recovered from different monocultured microbial and mixed infections in humans and animals. In health and disease, it is a key component of periodontal plaque due to its abundance and its ability to coaggregate with other bacteria species in the oral cavity.
Oral microbiology is the study of the microorganisms (microbiota) of the oral cavity and their interactions between oral microorganisms or with the host. The environment present in the human mouth is suited to the growth of characteristic microorganisms found there. It provides a source of water and nutrients, as well as a moderate temperature. Resident microbes of the mouth adhere to the teeth and gums to resist mechanical flushing from the mouth to stomach where acid-sensitive microbes are destroyed by hydrochloric acid.
Oral ecology is the microbial ecology of the microorganisms found in mouths. Oral ecology, like all forms of ecology, involves the study of the living things found in oral cavities as well as their interactions with each other and with their environment. Oral ecology is frequently investigated from the perspective of oral disease prevention, often focusing on conditions such as dental caries, candidiasis ("thrush"), gingivitis, periodontal disease, and others. However, many of the interactions between the microbiota and oral environment protect from disease and support a healthy oral cavity. Interactions between microbes and their environment can result in the stabilization or destabilization of the oral microbiome, with destabilization believed to result in disease states. Destabilization of the microbiome can be influenced by several factors, including diet changes, drugs or immune system disorders.
Anaerobic infections are caused by anaerobic bacteria. Obligately anaerobic bacteria do not grow on solid media in room air ; facultatively anaerobic bacteria can grow in the presence or absence of air. Microaerophilic bacteria do not grow at all aerobically or grow poorly, but grow better under 10% carbon dioxide or anaerobically. Anaerobic bacteria can be divided into strict anaerobes that can not grow in the presence of more than 0.5% oxygen and moderate anaerobic bacteria that are able of growing between 2 and 8% oxygen. Anaerobic bacteria usually do not possess catalase, but some can generate superoxide dismutase which protects them from oxygen.
Bifidobacterium is a genus of gram-positive, nonmotile, often branched anaerobic bacteria. They are ubiquitous inhabitants of the gastrointestinal tract though strains have been isolated from the vagina and mouth of mammals, including humans. Bifidobacteria are one of the major genera of bacteria that make up the gastrointestinal tract microbiota in mammals. Some bifidobacteria are used as probiotics.
Brachyspira pilosicoli is a gram-negative, anaerobic, host-associated spirochete that colonizes the intestinal tract of animals and humans. It appears as a characteristic "false brush border" due to its end-on attachment to enterocytes of the colon where it interferes with intestinal absorption. B. pilosicoli is unique from other Brachyspira species because it colonizes a variety of domestic animals including pigs, chickens, dogs, wild birds, rodents, and humans. It is the causative agent of intestinal spirochetosis in pigs, chickens, and humans. In particular, B. pilosicoli has been described as an important colonic pathogen of pigs and chickens, causing colitis and diarrhea resulting in depressed rates of growth and impaired production on farms where infections with B. pilosicoli may be endemic. Bacterial attachment disrupts the colonic enterocytes and associated villi, causing the symptoms characteristic of intestinal spirochetosis. Additionally, B. pilosicoli is associated with clinical disease in human infections where it has implications for public health.
Akkermansia muciniphila is a human intestinal symbiont, isolated from human feces. It is a mucin-degrading bacterium belonging to the genus, Akkermansia, discovered in 2004 by Muriel Derrien and Willem de Vos at Wageningen University of the Netherlands. It belongs to the phylum Verrucomicrobiota and its type strain is MucT. It is under preliminary research for its potential association with metabolic disorders.
The human digestive system consists of the gastrointestinal tract plus the accessory organs of digestion. Digestion involves the breakdown of food into smaller and smaller components, until they can be absorbed and assimilated into the body. The process of digestion has three stages: the cephalic phase, the gastric phase, and the intestinal phase.
Campylobacter showae is a Gram-negative, chemoheterotrophic, microaerophilic, motile bacteria belonging to the Campylobacter Genus. The type strain of this species, SU A4, was first isolated from plaque samples taken from the gingival crevices of the human oral cavity but has since also been found in colonic tissues and stool. Since its discovery, C. showae has been implicated in various medical conditions including Crohn's disease, periodontitis, inflammatory bowel disease, and ulcerative colitis due to its pathogenic nature.
Bifidobacterium bifidum is a bacterial species of the genus Bifidobacterium. B. bifidum is one of the most common probiotic bacteria that can be found in the body of mammals, including humans.
Bifidobacterium breve is a bacterial species of the genus Bifidobacterium which has probiotic properties. Bifidobacteria are a type of bacteria that live symbiotically in the intestines of humans. They have been used to treat a number of conditions including constipation, diarrhea, irritable bowel syndrome and even the cold and flu. Some of these uses have been backed up by scientific research, but others have not. B. breve is a gram positive, anaerobic, rod shaped organism that is non motile and forms branches with its neighbors.
The intestinal mucosal barrier, also referred to as intestinal barrier, refers to the property of the intestinal mucosa that ensures adequate containment of undesirable luminal contents within the intestine while preserving the ability to absorb nutrients. The separation it provides between the body and the gut prevents the uncontrolled translocation of luminal contents into the body proper. Its role in protecting the mucosal tissues and circulatory system from exposure to pro-inflammatory molecules, such as microorganisms, toxins, and antigens is vital for the maintenance of health and well-being. Intestinal mucosal barrier dysfunction has been implicated in numerous health conditions such as: food allergies, microbial infections, irritable bowel syndrome, inflammatory bowel disease, celiac disease, metabolic syndrome, non-alcoholic fatty liver disease, diabetes, and septic shock.
Bilophila wadsworthia is a Gram-negative, obligately anaerobic, catalase-positive, bile-resistant, and asaccharolytic bacillus. Approximately 75% of B. wadsworthia strains are urease positive. B. wadsworthia is linked to various diseases and is not well known due to frequent misidentification of the bacteria, and the National Center for Biotechnology Information is including it the phylum of Proteobacteria. The two unique characteristics of B. wadsworthia are the utilisation of the sulfated amino acid taurine in the production of hydrogen sulfide and the rapid catalase reaction. This bacterium is susceptible to the β-lactam antibiotics imipenem, cefoxitin, and ticarcillin.