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PPLO
''Mycoplasma'' is a genus of bacteria that, like the other members of the class ''Mollicutes'', lack a cell wall around their cell membranes. Peptidoglycan (murein) is absent. This characteristic makes them naturally resistant to antibiotics that target cell wall synthesis (like the beta-lactam antibiotics). They can be parasitic or saprotrophic. Several species are pathogenic in humans, including '' M. pneumoniae'', which is an important cause of "walking" pneumonia and other respiratory disorders, and '' M. genitalium'', which is believed to be involved in pelvic inflammatory diseases. ''Mycoplasma'' species (like the other species of the class ''Mollicutes'') are among the smallest organisms yet discovered, can survive without oxygen, and come in various shapes. For example, ''M. genitalium'' is flask-shaped (about 300 x 600 nm), while ''M. pneumoniae'' is more elongated (about 100 x 1000 nm), many ''Mycoplasma'' species are coccoid. Hundreds of ''Mycoplasma'' species i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mycoplasma Pneumoniae
''Mycoplasma pneumoniae'' is a very small bacterium in the class Mollicutes. It is a human pathogen that causes the disease mycoplasma pneumonia, a form of atypical bacterial pneumonia related to cold agglutinin disease. ''M. pneumoniae'' is characterized by the absence of a peptidoglycan cell wall and resulting resistance to many antibacterial agents. The persistence of ''M. pneumoniae'' infections even after treatment is associated with its ability to mimic host cell surface composition. Discovery and history In 1898, Nocard and Roux isolated an agent assumed to be the cause of cattle pneumonia and named it ''microbe de la peripneumonie'' Microorganisms from other sources, having properties similar to the pleuropneumonia organism (PPO) of cattle, soon came to be known as pleuropneumonia-like organisms (PPLO), but their true nature remained unknown. Many PPLO were later proven to be the cause of pneumonias and arthritis in several lower animals. In 1944, Monroe Eaton had used ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mollicutes
Mollicutes is a class of bacteria distinguished by the absence of a cell wall. The word "Mollicutes" is derived from the Latin ''mollis'' (meaning "soft" or "pliable"), and ''cutis'' (meaning "skin"). Individuals are very small, typically only 0.2–0.3 μm (200-300 nm) in size and have a very small genome size. They vary in form, although most have sterols that make the cell membrane somewhat more rigid. Many are able to move about through gliding, but members of the genus ''Spiroplasma'' are helical and move by twisting. The best-known genus in the Mollicutes is ''Mycoplasma''. Colonies show the typical "fried-egg" appearance. Mollicutes are parasites of various animals and plants, living on or in the host's cells. Many cause diseases in humans, attaching to cells in the respiratory or urogenital tracts, particularly species of ''Mycoplasma'' and ''Ureaplasma''. Phytoplasma and ''Spiroplasma'' are plant pathogens associated with insect vectors. Whereas formerly the trivial n ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Peptidoglycan
Peptidoglycan or murein is a unique large macromolecule, a polysaccharide, consisting of sugars and amino acids that forms a mesh-like peptidoglycan layer outside the plasma membrane, the rigid cell wall (murein sacculus) characteristic of most bacteria (domain ''Bacteria''). The sugar component consists of alternating residues of β-(1,4) linked ''N''-acetylglucosamine (NAG) and ''N''-acetylmuramic acid (NAM). Attached to the ''N''-acetylmuramic acid is a oligopeptide chain made of three to five amino acids. The peptide chain can be cross-linked to the peptide chain of another strand forming the 3D mesh-like layer. Peptidoglycan serves a structural role in the bacterial cell wall, giving structural strength, as well as counteracting the osmotic pressure of the cytoplasm. This repetitive linking results in a dense peptidoglycan layer which is critical for maintaining cell form and withstanding high osmotic pressures, and it is regularly replaced by peptidoglycan production. Pep ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Murein
Peptidoglycan or murein is a unique large macromolecule, a polysaccharide, consisting of sugars and amino acids that forms a mesh-like peptidoglycan layer outside the plasma membrane, the rigid cell wall (murein sacculus) characteristic of most bacteria (domain ''Bacteria''). The sugar component consists of alternating residues of β-(1,4) linked ''N''-acetylglucosamine (NAG) and ''N''-acetylmuramic acid (NAM). Attached to the ''N''-acetylmuramic acid is a oligopeptide chain made of three to five amino acids. The peptide chain can be cross-linked to the peptide chain of another strand forming the 3D mesh-like layer. Peptidoglycan serves a structural role in the bacterial cell wall, giving structural strength, as well as counteracting the osmotic pressure of the cytoplasm. This repetitive linking results in a dense peptidoglycan layer which is critical for maintaining cell form and withstanding high osmotic pressures, and it is regularly replaced by peptidoglycan production. Peptid ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mycoplasma Haemofelis
''Mycoplasma haemofelis'' (formerly ''Haemobartonella felis'') is a gram-negative epierythrocytic parasitic bacterium. It often appears in bloodsmears as small (0.6μm) coccoid bodies, sometimes forming short chains of three to eight organisms. It is usually the causative agent of feline infectious anemia (FIA) in the United States. The ~1.15 Mb genome contains a minimalistic assortment of genes limited to the most basic cellular functions. This leaves ''M. haemofelis'' inextricably dependent upon its host for the provision of amino acids, cholesterol, vitamins and fatty acids. The complex and specific conditions that the bacterium requires have made it impossible to culture outside a host thus far. Arthropod vectors are thought to be the primary source of infection, although ''M. haemofelis'' is also known to be transmitted from queen to kitten and following blood transfusion. Immunocompromization and/or coinfection with FeLV, FIV and other ''Mycoplasma'' species can exacerb ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mycoplasmataceae
Mycoplasmataceae is a family of bacteria in the order Mycoplasmatales. This family consists of the genera ''Mycoplasma'' and ''Ureaplasma''. In 1967, the order Mycoplasmatales was incorporated into the class Mollicutes. Many species are sexually transmitted and cause pelvic inflammatory disease. Taxonomy ''Mycoplasma'' ''Mycoplasma ''refers to a genus of bacteria that lack a cell wall and possess a three-layered cellular membrane. They can be parasitic or saprotrophic. Several species are sexually transmitted and pathogenic in humans. Others are found on cats, dogs, and barnyard fowl. ''Ureaplasma'' ''Ureaplasma'' is the second of two genera of bacteria belonging to the family Mycoplasmataceae. As the name implies, ureaplasma is urease positive. This genera is distinct from other genera in Mollicutes in that it hydrolyses urea for generation of ATP. ''Ureaplasma'' ''spp.'' as human pathogens Both ''Ureaplasma urealyticum'' and '' Ureaplasma parvum'' have been identified as ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mycoplasmatales
Mycoplasmataceae is a family of bacteria in the order Mycoplasmatales. This family consists of the genera ''Mycoplasma'' and ''Ureaplasma''. In 1967, the order Mycoplasmatales was incorporated into the class Mollicutes. Many species are sexually transmitted and cause pelvic inflammatory disease. Taxonomy ''Mycoplasma'' ''Mycoplasma ''refers to a genus of bacteria that lack a cell wall and possess a three-layered cellular membrane. They can be parasitic or saprotrophic. Several species are sexually transmitted and pathogenic in humans. Others are found on cats, dogs, and barnyard fowl. ''Ureaplasma'' ''Ureaplasma'' is the second of two genera of bacteria belonging to the family Mycoplasmataceae. As the name implies, ureaplasma is urease positive. This genera is distinct from other genera in Mollicutes in that it hydrolyses urea for generation of ATP. ''Ureaplasma'' ''spp.'' as human pathogens Both ''Ureaplasma urealyticum'' and ''Ureaplasma parvum'' have been identified as ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Albert Bernhard Frank
Albert Bernhard Frank (January 17, 1839 – September 27, 1900) was a German botanist, plant pathologist, and mycologist, born in Dresden. He is credited with coining the term ''mycorrhiza'' in his 1885 paper "Über die auf Wurzelsymbiose beruhende Ernährung gewisser Bäume durch unterirdische Pilze". Frank was commissioned to develop practical methods for truffle cultivation by the King of Prussia (Wilhelm I). Although this project was not successful, it led to his elucidation of the nature and development of mycorrhizae. The history and impacts of Frank's work on mycorrhizae were reviewed by Trappe. The bacterial genus ''Frankia'' and family ''Frankiaceae'' were named after him.Prokaryotic symbionts in plants by Katharina Pawlowskip. 107/ref> In 1877, Albert Frank coined the term "symbiosis" (German: Symbiose) to describe the nature of lichens. He died in Berlin. Works * ''Pflanzen-Tabellen zur leichten, schnellen und sicheren Bestimmung der höheren Gewächse Nord-und M ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Colonial Morphology
In microbiology, colonial morphology refers to the visual appearance of bacterial colony, bacterial or fungus, fungal colonies on an agar plate. Examining colonial morphology is the first step in the identification of an unknown microbe. The systematic assessment of the colonies' appearance, focusing on aspects like size, shape, colour, opacity, and consistency, provides clues to the identity of the organism, allowing microbiologists to select appropriate tests to provide a definitive identification. Procedure When a specimen arrives in the microbiology laboratory, it is inoculated into an agar plate and placed in an Incubator (microbiology), incubator to encourage microbial growth. Because the appearance of microbial colonies changes as they grow, colonial morphology is examined at a specific time after the plate is inoculated. Usually, the plate is read at 18–24 hours post-inoculation, but times may differ for slower-growing organisms like fungi. The microbiologist examines th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Contagious Bovine Pleuropneumonia
Contagious bovine pleuropneumonia (CBPP – also known as lung plague), is a contagious bacterial disease that afflicts the lungs of cattle, buffalo, zebu, and yaks. It is caused by the bacterium ''Mycoplasma mycoides'', and the symptoms are pneumonia and inflammation of the lung membranes. The incubation period is 20 to 123 days. It was particularly widespread in the United States in 1879, affecting herds from several states. The outbreak was so severe that it resulted in a trade embargo by the British government, blocking U.S. cattle exports to Britain and Canada. This prompted the United States to establish the Bureau of Animal Industry, set up in 1884 to eradicate the disease, which it succeeded in doing by 1892. Louis Willems, a Belgian doctor, began pioneering work in the 1850s on animal inoculation against the disease. The bacteria are widespread in Africa, the Middle East, Southern Europe, as well as parts of Asia. It is an airborne species, and can travel up to several k ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nanometers
330px, Different lengths as in respect to the molecular scale. The nanometre (international spelling as used by the International Bureau of Weights and Measures; SI symbol: nm) or nanometer (American and British English spelling differences#-re, -er, American spelling) is a units of measurement, unit of length in the International System of Units (SI), equal to one billionth (short scale) of a metre () and to 1000 picometres. One nanometre can be expressed in scientific notation as , and as metres. History The nanometre was formerly known as the millimicrometre – or, more commonly, the millimicron for short – since it is of a micron (micrometre), and was often denoted by the symbol mμ or (more rarely and confusingly, since it logically should refer to a ''millionth'' of a micron) as μμ. Etymology The name combines the SI prefix ''nano-'' (from the Ancient Greek , ', "dwarf") with the parent unit name ''metre'' (from Greek , ', "unit of measurement"). ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mycoplasma Amphoriforme
''Mycoplasma amphoriforme'' is a species of bacteria in the genus ''Mycoplasma''. This genus of bacteria lacks a cell wall around their cell membrane. Without a cell wall, they are unaffected by many common antibiotics such as penicillin or other beta-lactam antibiotics that target cell wall synthesis. Mycoplasma are the smallest bacterial cells yet discovered, can survive without oxygen and are typically about 0.1 µm in diameter. It has been found in human respiratory infections and is associated with chronic bronchitis in immunosuppressed patients. It has been observed to possess gliding motility, a protruding polar tip resembling that of M. gallisepticum, and cytoskeletal structure at its polar tip similar to M. pneumonia's. Those infected show symptoms of lower respiratory tract infections such as increased respiratory rates and increased pulse rates. The type strain is strain A39 = ATCC BAA-992 = NCTC 11740 . See also * Lower respiratory tract infection Lower ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
