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Acinetobacter Johnsonii
''Acinetobacter calcoaceticus'' is a bacterial species of the genus ''Acinetobacter''. It is a nonmotile, Gram-negative coccobacillus. It grows under aerobic conditions, is catalase positive and oxidase negative. ''A. calcoaceticus'' is a part of the A. calcoaceticus-A. baumannii complex together with ''Acinetobacter baumannii'', ''Acinetobacter nosocomialis'', ''Acinetobacter pitti'' and ''Acinetobacter seifertii''. Habitat ''A. calcoaceticus'' is a soil bacterium. It has been shown to be in the human body's in moist areas like the mouth, groin, respiratory tract, and gastrointestinal tract. It is also present in Tiger mosquito (''Aedes albopictus'') microflora. Metabolism Phloroglucinol carboxylic acid is a degradation product excreted by ''A. calcoaceticus'' grown on (+)-catechin Catechin is a flavan-3-ol, a type of secondary metabolite providing antioxidant roles in plants. It belongs to the subgroup of polyphenols called flavonoids. The name of the catechin chemical f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Martinus Beijerinck
Martinus Willem Beijerinck (, 16 March 1851 – 1 January 1931) was a Dutch microbiologist and botanist who was one of the founders of virology and environmental microbiology. He is credited with the co-discovery of viruses A virus is a submicroscopic infectious agent that replicates only inside the living cells of an organism. Viruses infect all life forms, from animals and plants to microorganisms, including bacteria and archaea. Viruses are found in almo ... (1898), which he called "''contagium vivum fluidum''". Life Early life and education Born in Amsterdam, Beijerinck studied at the Technical School of Delft, where he was awarded the degree of biology in 1872. He obtained his Doctor of Science degree from the University of Leiden in 1877. At the time, Delft, then a List of institutions using the term "institute of technology" or "polytechnic", Polytechnic, did not have the right to confer doctorates, so Leiden did this for them. He became a teacher in microb ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
1911 In Science
The year 1911 in science and technology involved some significant events, listed below. Astronomy * June 28 – The Nakhla meteorite (from Mars) lands in the area of Alexandria, Egypt, purportedly killing a dog. It suggests the first signs of water on Mars. Conservation * May 19 – Parks Canada, the world's first national park service, is established as the Dominion Parks Branch under the Department of the Interior. * July 7 – The United States, Russia, the United Kingdom and Japan, meeting in Washington, D.C., sign the North Pacific Fur Seal Convention of 1911, prohibiting open-water seal hunting of the endangered fur seal in the North Pacific Ocean, the first international treaty to address wildlife conservation issues. In the next six years, the seal population increases by 30%. Geology * January 3 – 1911 Kebin earthquake: An earthquake of 7.7 moment magnitude strikes near Almaty in Russian Turkestan. Exploration * July 24 – American explorer Hiram Bingham III r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acinetobacter
''Acinetobacter'' is a genus of Gram-negative bacteria belonging to the wider class of Gammaproteobacteria. ''Acinetobacter'' species are oxidase-negative, exhibit twitching motility, and occur in pairs under magnification. They are important soil organisms, where they contribute to the mineralization of, for example, aromatic compounds. ''Acinetobacter'' species are a key source of infection in debilitated patients in the hospital, in particular the species '' Acinetobacter baumannii''. Description Species of the genus ''Acinetobacter'' are strictly aerobic, nonfermentative, Gram-negative bacilli. They show mostly a coccobacillary morphology on nonselective agar. Rods predominate in fluid media, especially during early growth. The morphology of ''Acinetobacter'' species can be quite variable in Gram-stained human clinical specimens, and cannot be used to differentiate ''Acinetobacter'' from other common causes of infection. Most strains of ''Acinetobacter'', except som ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gram-negative
Gram-negative bacteria are bacteria that, unlike gram-positive bacteria, do not retain the crystal violet stain used in the Gram staining method of bacterial differentiation. Their defining characteristic is that their cell envelope consists of a thin peptidoglycan cell wall sandwiched between an inner ( cytoplasmic) membrane and an outer membrane. These bacteria are found in all environments that support life on Earth. Within this category, notable species include the model organism '' Escherichia coli'', along with various pathogenic bacteria, such as '' Pseudomonas aeruginosa'', '' Chlamydia trachomatis'', and '' Yersinia pestis''. They pose significant challenges in the medical field due to their outer membrane, which acts as a protective barrier against numerous antibiotics (including penicillin), detergents that would normally damage the inner cell membrane, and the antimicrobial enzyme lysozyme produced by animals as part of their innate immune system. Furthe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coccobacillus
Bacterial cellular morphologies are the shapes that are characteristic of various types of bacteria and often key to their identification. Their direct examination under a light microscope enables the classification of these bacteria (and archaea). Generally, the basic morphologies are spheres (coccus) and round-ended cylinders or rod shaped (bacillus). But, there are also other morphologies such as helically twisted cylinders (example '' Spirochetes''), cylinders curved in one plane (selenomonads) and unusual morphologies (the square, flat box-shaped cells of the Archaean genus '' Haloquadratum)''. Other arrangements include pairs, tetrads, clusters, chains and palisades. Types Coccus A coccus (plural ''cocci'', from the Latin ''coccinus'' (scarlet) and derived from the Greek ''kokkos'' (berry)), is any microorganism (usually bacteria) whose overall shape is spherical or nearly spherical. Coccus refers to the shape of the bacteria and can contain multiple genera, such as s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aedes Albopictus
''Aedes albopictus'' (synonym (taxonomy), synonym ''Stegomyia albopicta''), from the mosquito (Culicidae) family (biology), family, also known as the (Asian) tiger mosquito or forest mosquito, is a mosquito native to the tropical and Subtropics, subtropical areas of Southeast Asia. In the past few centuries, however, this species has spread to many countries through the transport of goods and international travel. It is characterized by the white bands on its legs and body. This mosquito has become a significant pest in many communities because it closely associates with humans (rather than living in wetlands), and typically flies and feeds in the daytime in addition to at dusk and dawn. The insect is called a tiger mosquito as it has stripes, as does a tiger. ''Ae. albopictus'' is an epidemiology, epidemiologically important Vector (epidemiology), vector for the Transmission (medicine), transmission of many viral pathogens, including the Yellow fever, yellow fever virus, d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phloroglucinol Carboxylic Acid
Phloroglucinol carboxylic acid, also called ‘Phloroglucinic acid’ or simply ‘PGCA’, is a trihydroxybenzoic acid, a type of phenolic acid. It can be encountered in nature were it is produced by plants or microorganisms. Structurally, the molecule can be perceived as Gallic acid in which the 2 hydroxy groups at positions 3 and 5 respectively on the benzene ring backbone have been moved “up” to positions 2 and 6, closely neighboring the carboxylic acid functional group. Salts and esters of PGCA (e.g. potassium salt or methyl ester) are known as Phloroglucinates. It is produced by ''Pseudomonas fluorescens''. It is a catechin degradation product excreted by the bacterium ''Acinetobacter calcoaceticus ''Acinetobacter calcoaceticus'' is a bacterial species of the genus '' Acinetobacter''. It is a nonmotile, Gram-negative coccobacillus. It grows under aerobic conditions, is catalase positive and oxidase negative. ''A. calcoaceticus'' is a part ...'', a species of bacte ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Catechin
Catechin is a flavan-3-ol, a type of secondary metabolite providing antioxidant roles in plants. It belongs to the subgroup of polyphenols called flavonoids. The name of the catechin chemical family derives from ''catechu'', which is the tannic juice or boiled extract of ''Mimosa catechu'' (''Acacia catechu'' L.f.). Chemistry Catechin possesses two benzene rings (called the A and B rings) and a dihydropyran heterocycle (the C ring) with a hydroxyl group on carbon 3. The A ring is similar to a resorcinol moiety while the B ring is similar to a catechol moiety. There are two chirality (chemistry), chiral centers on the molecule on carbons 2 and 3. Therefore, it has four diastereoisomers. Two of the isomers are in trans configuration, ''trans'' configuration and are called ''catechin'' and the other two are in cis configuration, ''cis'' configuration and are called ''epicatechin''. The most common catechin isomer is (+)-catechin. The other stereoisomer is (−)-catechin or ''en ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
