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Bifidobacterium Vespertilionis
''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 ('' B. dentium'') 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. Before the 1960s, ''Bifidobacterium'' species were collectively referred to as ''Lactobacillus bifidus''. History In 1899, Henri Tissier, a French pediatrician at the Pasteur Institute in Paris, isolated a bacterium characterised by a Y-shaped morphology ("bifid") in the intestinal microbiota of breast-fed infants and named it "bifidus". In 1907, Élie Metchnikoff, deputy director at the Pasteur Institute, propounded the theory that lactic acid bacteria are beneficial to human health. Metchnikoff observed that the longevity of Bulgarians was the result of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sigurd Orla-Jensen
Sigurd ( ) or Siegfried (Middle High German: ''Sîvrit'') is a legendary hero of Germanic heroic legend, who killed a dragon — known in Nordic tradition as Fafnir () — and who was later murdered. In the Nordic countries, he is referred to with the epithet "Fáfnir's bane" (, , , ), and is also widely known as "the Dragon Slayer". In both the Norse and continental Germanic traditions, Sigurd is portrayed as dying as the result of a quarrel between his wife (Gudrun/Kriemhild) and another woman, Brunhild, whom he has tricked into marrying the Burgundian king Gunnar/Gunther. His slaying of a dragon and possession of the hoard of the Nibelungen is also common to both traditions. In other respects, however, the two traditions appear to diverge. The most important works to feature Sigurd are the , the ''Völsunga saga'', and the ''Poetic Edda''. He also appears in numerous other works from both Germany and Scandinavia, including a series of medieval and early modern Scandinavi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Élie Metchnikoff
Ilya Ilyich Mechnikov (; – 15 July 1916), also spelled Élie Metchnikoff, was a zoologist from the Russian Empire of Moldavian noble ancestry and alshereat archive.org best known for his research in immunology (study of immune systems) and thanatology (study of death). Belkin, a Russian science historian, explains why Metchnikoff himself, in his Nobel autobiography – and subsequently, many other sources – mistakenly cited his date of birth as 16 May instead of 15 May. Metchnikoff made the mistake of adding 13 days to 3 May, his Old Style birthday, as was the convention in the 20th century. But since he had been born in the 19th century, only 12 days should have been added. He and Paul Ehrlich were jointly awarded the 1908 Nobel Prize in Physiology or Medicine "in recognition of their work on immunity". Mechnikov was born in a region of the Russian Empire that is today part of modern-day Ukraine to a Moldavian noble father and a Ukrainian-Jewish mother, and later on ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Microaerophilic
A microaerophile is a microorganism that requires environments containing lower levels of dioxygen than that are present in the atmosphere (i.e. < 21% O2; typically 2–10% O2) for optimal growth. A more restrictive interpretation requires the microorganism to be obligate in this requirement. Many microaerophiles are also capnophiles, requiring an elevated concentration of (e.g. 10% CO2 in the case of '' Campylobacter'' ). The original ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oxic
Hypoxia (''hypo'': 'below', ''oxia'': 'oxygenated') refers to low oxygen conditions. Hypoxia is problematic for air-breathing organisms, yet it is essential for many anaerobic organisms. Hypoxia applies to many situations, but usually refers to the atmosphere and natural waters. Atmospheric hypoxia Atmospheric hypoxia occurs naturally at high altitudes. Total atmospheric pressure decreases as altitude increases, causing a lower partial pressure of oxygen, which is defined as hypobaric hypoxia. Oxygen remains at 20.9% of the total gas mixture, differing from hypoxic hypoxia, where the percentage of oxygen in the air (or blood) is decreased. This is common in the sealed burrows of some subterranean animals, such as blesmols. Atmospheric hypoxia is also the basis of altitude training, which is a standard part of training for elite athletes. Several companies mimic hypoxia using normobaric artificial atmosphere. Aquatic hypoxia An aquatic system lacking dissolved oxygen (0% ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Catabolism
Catabolism () is the set of metabolic pathways that breaks down molecules into smaller units that are either oxidized to release energy or used in other anabolic reactions. Catabolism breaks down large molecules (such as polysaccharides, lipids, nucleic acids, and proteins) into smaller units (such as monosaccharides, fatty acids, nucleotides, and amino acids, respectively). Catabolism is the breaking-down aspect of metabolism, whereas anabolism is the building-up aspect. Cells use the monomers released from breaking down polymers to either construct new polymer molecules or degrade the monomers further to simple waste products, releasing energy. Cellular wastes include lactic acid, acetic acid, carbon dioxide, ammonia, and urea. The formation of these wastes is usually an oxidation process involving a release of chemical free energy, some of which is lost as heat, but the rest of which is used to drive the synthesis of adenosine triphosphate (ATP). This molecule acts as a way ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Galactooligosaccharide
Galactooligosaccharides (GOS), also known as oligogalactosyllactose, oligogalactose, oligolactose or transgalactooligosaccharides (TOS), belong to the group of prebiotics. Prebiotics are defined as non-digestible food ingredients that beneficially affect the host by stimulating the growth and/or activity of beneficial bacteria in the colon. GOS occurs in commercially available products such as food for both infants and adults. Chemistry The composition of the galactooligosaccharide fraction varies in chain length and type of linkage between the monomer units. Galactooligosaccharides are produced through the enzymatic conversion of lactose, a component of bovine milk. A range of factors come into play when determining the yield, style, and type of GOS produced. These factors include: * enzyme source * enzyme dosage * feeding stock (lactose) concentration * origins of the lactose * process involved (e.g. free or immobilized enzyme) * reaction conditions impacting the processing ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fructooligosaccharide
Fructooligosaccharides (FOS) also sometimes called oligofructose or oligofructan, are oligosaccharide fructans, used as an alternative sweetener. FOS exhibits sweetness levels between 30 and 50 percent of sugar in commercially prepared syrups. It occurs naturally, and its commercial use emerged in the 1980s in response to demand for healthier and calorie-reduced foods. Chemistry Two different classes of fructooligosaccharide (FOS) mixtures are produced commercially, based on inulin degradation or transfructosylation processes. FOS can be produced by degradation of inulin, or polyfructose, a polymer of D-fructose residues linked by β(2→1) bonds with a terminal α(1→2) linked D-glucose. The degree of polymerization of inulin ranges from 10 to 60. Inulin can be degraded enzymatically or chemically to a mixture of oligosaccharides with the general structure Glu–Frun (abbrev. GFn) and Frum (Fm), with n and m ranging from 1 to 7. This process also occurs to some extent in n ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Human Milk Oligosaccharide
Human milk oligosaccharides (HMOs), also known as human milk glycans, are short polymers of Monosaccharide, simple sugars that can be found in high concentrations in Breast milk, human breast milk. Human milk oligosaccharides promote the development of the immune system, can reduce the risk of pathogen infections and improve brain development and cognition. The HMO profile of human breast milk shapes the gut microbiota of the infant by selectively stimulating Bifidobacterium, bifidobacteria and other bacteria. Functions In contrast to the other components of breast milk that are absorbed by the infant through breastfeeding, HMOs are Digestion, indigestible for the nursing child. However, they have a Prebiotic (nutrition), prebiotic effect and serve as food for intestinal bacteria, especially Bifidobacterium, bifidobacteria. The dominance of these intestinal bacteria in the gut reduces the colonization with Pathogen#Pathogenicity, pathogenic bacteria (probiosis) and thereby pro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phylotype
In taxonomy, a phylotype is an observed similarity used to classify a group of organisms by their phenetic relationship. This phenetic similarity, particularly in the case of asexual organisms, may reflect the evolutionary relationships. The term is rank-neutral, so that phylotypes can be described at different levels, such as species, class, 97% genetic similarity, or homology. The term is often used in microbiology, since the genomes of prokaryotes, which freely exchange genetic material, do not lend themselves to classification via Linnean taxonomy as easily as do many eukaryotes The eukaryotes ( ) constitute the domain of Eukaryota or Eukarya, organisms whose cells have a membrane-bound nucleus. All animals, plants, fungi, seaweeds, and many unicellular organisms are eukaryotes. They constitute a major group of ... such as plants and animals. See also * Phylotypic stage References Taxonomy {{Biology-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oligosaccharide
An oligosaccharide (; ) is a carbohydrate, saccharide polymer containing a small number (typically three to ten) of monosaccharides (simple sugars). Oligosaccharides can have many functions including Cell–cell recognition, cell recognition and cell adhesion. They are normally present as glycans: oligosaccharide chains are linked to lipids or to compatible amino acid side chains in proteins, by ''N''- or ''O''-glycoside, glycosidic bonds. ''N''-Linked oligosaccharides are always pentasaccharides attached to asparagine via a beta linkage to the amine nitrogen of the side chain.. Alternately, O-linked glycosylation, ''O''-linked oligosaccharides are generally attached to threonine or serine on the alcohol group of the side chain. Not all natural oligosaccharides occur as components of glycoproteins or glycolipids. Some, such as the raffinose series, occur as storage or transport carbohydrates in plants. Others, such as maltodextrins or cellodextrins, result from the microbial break ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carbohydrate
A carbohydrate () is a biomolecule composed of carbon (C), hydrogen (H), and oxygen (O) atoms. The typical hydrogen-to-oxygen atomic ratio is 2:1, analogous to that of water, and is represented by the empirical formula (where ''m'' and ''n'' may differ). This formula does not imply direct covalent bonding between hydrogen and oxygen atoms; for example, in , hydrogen is covalently bonded to carbon, not oxygen. While the 2:1 hydrogen-to-oxygen ratio is characteristic of many carbohydrates, exceptions exist. For instance, uronic acids and deoxy-sugars like fucose deviate from this precise stoichiometric definition. Conversely, some compounds conforming to this definition, such as formaldehyde and acetic acid, are not classified as carbohydrates. The term is predominantly used in biochemistry, functioning as a synonym for saccharide (), a group that includes sugars, starch, and cellulose. The saccharides are divided into four chemical groups: monosaccharides, disaccharides, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fructose-6-phosphate Phosphoketolase
Fructose 6-phosphate (sometimes called the Neuberg ester) is a derivative of fructose, which has been phosphorylated at the 6-hydroxy group. It is one of several possible fructosephosphates. The β-D-form of this compound is very common in cells. The great majority of glucose is converted to fructose 6-phosphate upon entering a cell. Fructose is predominantly converted to fructose 1-phosphate by fructokinase following cellular import. History The name ''Neuberg ester'' comes from the German biochemist Carl Neuberg. In 1918, he found that the compound (later identified as fructose 6-phosphate) was produced by mild acid hydrolysis of fructose 2,6-bisphosphate.Fruton, Joseph S. ''Proteins, Enzymes, Genes: The Interplay of Chemistry and Biology''. Yale University Press: New Haven, 1999. p 292 In glycolysis Fructose 6-phosphate lies within the glycolysis metabolic pathway and is produced by isomerisation of glucose 6-phosphate. It is in turn further phosphorylated to fructose-1,6 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
