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Kauffman–White Classification
The Kauffmann–White classification or Kauffmann and White classification scheme is a system that classifies the genus ''Salmonella'' into serotypes, based on surface antigens. It is named after Philip Bruce White and Fritz Kauffmann. First the "O" antigen type is determined based on oligosaccharides associated with lipopolysaccharide. Then the "H" antigen is determined based on flagellar proteins (H is short for the German ''Hauch'' meaning "breath" or "mist"; O stands for German ''ohne'' meaning "without"). Since ''Salmonella'' typically exhibit phase variation In biology, phase variation is a method for dealing with rapidly varying environments without requiring random mutation. It involves the variation of protein expression, frequently in an on-off fashion, within different parts of a bacterial populati ... between two motile phenotypes, different "H" antigens may be expressed. Salmonella that can express only one "H" antigen phase consequently have motile and non-motile phen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Salmonella
''Salmonella'' is a genus of rod-shaped (bacillus) Gram-negative bacteria of the family Enterobacteriaceae. The two species of ''Salmonella'' are ''Salmonella enterica'' and ''Salmonella bongori''. ''S. enterica'' is the type species and is further divided into six subspecies that include over 2,600 serotypes. ''Salmonella'' was named after Daniel Elmer Salmon (1850–1914), an American veterinary surgeon. ''Salmonella'' species are non-spore-forming, predominantly motile enterobacteria with cell diameters between about 0.7 and 1.5 μm, lengths from 2 to 5 μm, and peritrichous flagella (all around the cell body, allowing them to move). They are chemotrophs, obtaining their energy from oxidation and reduction reactions, using organic sources. They are also facultative anaerobes, capable of generating ATP with oxygen ("aerobically") when it is available, or using other electron acceptors or fermentation ("anaerobically") when oxygen is not available. ''Salmonella'' spe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Serotype
A serotype or serovar is a distinct variation within a species of bacteria or virus or among immune cells of different individuals. These microorganisms, viruses, or cells are classified together based on their surface antigens, allowing the epidemiologic classification of organisms to the subspecies level. A group of serovars with common antigens is called a serogroup or sometimes ''serocomplex''. Serotyping often plays an essential role in determining species and subspecies. The ''Salmonella'' genus of bacteria, for example, has been determined to have over 2600 serotypes. ''Vibrio cholerae'', the species of bacteria that causes cholera, has over 200 serotypes, based on cell antigens. Only two of them have been observed to produce the potent enterotoxin that results in cholera: O1 and O139. Serotypes were discovered by the American microbiologist Rebecca Lancefield in 1933. Role in organ transplantation The immune system is capable of discerning a cell as being 'self' or 'n ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Antigens
In immunology, an antigen (Ag) is a molecule or molecular structure or any foreign particulate matter or a pollen grain that can bind to a specific antibody or T-cell receptor. The presence of antigens in the body may trigger an immune response. The term ''antigen'' originally referred to a substance that is an antibody generator. Antigens can be proteins, peptides (amino acid chains), polysaccharides (chains of monosaccharides/simple sugars), lipids, or nucleic acids. Antigens are recognized by antigen receptors, including antibodies and T-cell receptors. Diverse antigen receptors are made by cells of the immune system so that each cell has a specificity for a single antigen. Upon exposure to an antigen, only the lymphocytes that recognize that antigen are activated and expanded, a process known as clonal selection. In most cases, an antibody can only react to and bind one specific antigen; in some instances, however, antibodies may cross-react and bind more than one antigen. T ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Philip Bruce White
Philip Bruce White (29 December 1891 – 19 March 1949) was a British microbiologist. In 1926, White published a schema for classifying salmonella bacteria based on serum.F. Kauffmann: ''Das Fundament.'' Munksgaard, Kopenhagen, 1978. This was later extended by the Danish microbiologist Fritz Kauffmann, the Kauffman–White classification. White became a fellow of the Royal Society Fellowship of the Royal Society (FRS, ForMemRS and HonFRS) is an award granted by the judges of the Royal Society of London to individuals who have made a "substantial contribution to the improvement of natural science, natural knowledge, incl ... on 20 March 1941. White died in London. Websites Entryat the Royal Society * References People from Bangor, Gwynedd People educated at Friars School, Bangor 1891 births 1949 deaths British microbiologists Fellows of the Royal Society {{Microbiology-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fritz Kauffmann
Fritz originated as a German nickname for Friedrich, or Frederick (''Der Alte Fritz'', and ''Stary Fryc'' were common nicknames for King Frederick II of Prussia and Frederick III, German Emperor) as well as for similar names including Fridolin and, less commonly, Francis. Fritz (Fryc) was also a name given to German troops by the Entente powers equivalent to the derogative Tommy. Other common bases for which the name Fritz was used include the surnames Fritsche, Fritzsche, Fritsch, Frisch(e) and Frycz. Below is a list of notable people with the name "Fritz." Surname *Amanda Fritz (born 1958), retired registered psychiatric nurse and politician from Oregon *Al Fritz (1924–2013), American businessman *Ben Fritz (born 1981), American baseball coach *Betty Jane Fritz (1924–1994), one of the original players in the All-American Girls Professional Baseball League *Clemens Fritz (born 1980), German footballer *Edmund Fritz (before 1918–after 1932), Austrian actor, film director, a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oligosaccharides
An oligosaccharide (/ˌɑlɪgoʊˈsækəˌɹaɪd/; from the Greek ὀλίγος ''olígos'', "a few", and σάκχαρ ''sácchar'', "sugar") is a saccharide polymer containing a small number (typically two to ten) of monosaccharides (simple sugars). Oligosaccharides can have many functions including 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''-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 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 c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lipopolysaccharide
Lipopolysaccharides (LPS) are large molecules consisting of a lipid and a polysaccharide that are bacterial toxins. They are composed of an O-antigen, an outer core, and an inner core all joined by a covalent bond, and are found in the outer membrane of Gram-negative bacteria. Today, the term ''endotoxin'' is often used synonymously with LPS, although there are a few endotoxins (in the original sense of toxins that are inside the bacterial cell that are released when the cell disintegrates) that are not related to LPS, such as the so-called delta endotoxin proteins produced by '' Bacillus thuringiensis''. Lipopolysaccharides can have substantial impacts on human health, primarily through interactions with the immune system. LPS is a potent activator of the immune system and pyrogen (agent that causes fever). In severe cases, LPS can play a role in causing septic shock. In lower levels and over a longer time period, there is evidence LPS may play an important and harmful role ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Flagella
A flagellum (; ) is a hairlike appendage that protrudes from certain plant and animal sperm cells, and from a wide range of microorganisms to provide motility. Many protists with flagella are termed as flagellates. A microorganism may have from one to many flagella. A gram-negative bacterium ''Helicobacter pylori'' for example uses its multiple flagella to propel itself through the mucus lining to reach the stomach epithelium, where it may cause a gastric ulcer to develop. In some bacteria the flagellum can also function as a sensory organelle, being sensitive to wetness outside the cell. Across the three domains of Bacteria, Archaea, and Eukaryota the flagellum has a different structure, protein composition, and mechanism of propulsion but shares the same function of providing motility. The Latin word means " whip" to describe its lash-like swimming motion. The flagellum in archaea is called the archaellum to note its difference from the bacterial flagellum. Eukaryoti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phase Variation
In biology, phase variation is a method for dealing with rapidly varying environments without requiring random mutation. It involves the variation of protein expression, frequently in an on-off fashion, within different parts of a bacterial population. As such the phenotype can switch at frequencies that are much higher (sometimes >1%) than classical mutation rates. Phase variation contributes to virulence by generating heterogeneity. Although it has been most commonly studied in the context of immune evasion, it is observed in many other areas as well and is employed by various types of bacteria, including ''Salmonella'' species. ''Salmonella'' use this technique to switch between different types of the protein flagellin. As a result, flagella with different structures are assembled. Once an adaptive response has been mounted against one type of flagellin, or if a previous encounter has left the adaptive immune system ready to deal with one type of flagellin, switching types renders ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pathogenic Escherichia Coli
''Escherichia coli'' ( Anglicized to ; commonly abbreviated ''E. coli'') is a gram-negative, rod-shaped bacterium that is commonly found in the lower intestine of warm-blooded organisms (endotherms). Most ''E. coli'' strains are harmless, but pathogenic varieties cause serious food poisoning, septic shock, meningitis, or urinary tract infections in humans. Unlike normal flora ''E. coli'', the pathogenic varieties produce toxins and other virulence factors that enable them to reside in parts of the body normally not inhabited by ''E. coli'', and to damage host cells. These pathogenic traits are encoded by virulence genes carried only by the pathogens. Introduction ''E. coli'' and related bacteria constitute about 0.1% of gut flora, and fecal–oral transmission is the major route through which pathogenic strains of the bacterium cause disease. Cells are able to survive outside the body for only a limited amount of time, which makes them ideal indicator organisms to test en ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arthur Felix
Arthur Felix, FRS (3 April 1887 in Andrychów – 17 January 1956 in England) was a Polish-born microbiologist and serologist. Education and early life Arthur Felix was the son of Theodor Felix, who had an interest in printed textiles and who encouraged his son to study textile dye chemistry. Felix studied chemistry in Vienna and was awarded a Doctor of Science degree. After working in his father's textile printing factory, he returned to Vienna to study microbiology. Arthus Felix was Jewish; he became interested in Zionism during his student days in Vienna and later developed into an authority on Palestine. Career In 1915, Arthur Felix and Edmund Weil were Austrian medical officers working in a field laboratory in Sokal and discovered a bacillus in the urine of patients with typhus. They developed the Weil–Felix test for diagnosis of typhus and other rickettsial diseases. The use of the O and H symbols in the Kauffman–White classification originates from the research by E ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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