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Bradyrhizobium Japonicum
''Bradyrhizobium japonicum'' is a species of legume- root nodulating, microsymbiotic nitrogen-fixing bacteria. The species is one of many Gram-negative, rod-shaped bacteria commonly referred to as rhizobia. Within that broad classification, which has three groups, taxonomy studies using DNA sequencing indicate that ''B. japonicum'' belongs within homology group II. Uses Agriculture ''B. japonicum'' is added to legume seed to improve crop yields, particularly in areas where the bacterium is not native (e.g. Arkansas soils). Often the inoculate is adhered to the seeds prior to planting using a sugar solution. Research A strain of ''B. japonicum'', USDA110, has been in use as a model organism since 1957. It is widely used to study molecular genetics, plant physiology, and plant ecology due to its relatively superior symbiotic nitrogen-fixation activity with soybean (i.e. compared to other rhizobia species). Its entire genome was sequenced in 2002, revealing that the specie ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oskar Von Kirchner
Emil Otto Oskar von Kirchner (15 September 1851, in Breslau – 25 April 1925, in Venice) was a German botanist and agronomist. He studied botany at the University of Breslau, receiving his doctorate in 1873 with a dissertation on the botanical writings of Theophrastus. After graduation, he worked as an assistant at the pomology institute of the agricultural academy in Proskau. From 1881 to 1917 he was a professor of botany at the Agricultural Academy in Hohenheim. The phycological genera; ''Kirchneria'' (in the family Polypodiopsida), ''Kirchneriella'' (in the family Selenastraceae), ''Kirchneriellopsis'' and ''Kirchneriellosaccus'', all commemorate his name. Selected works * ''Die mikroskopische Pflanzen-und Thierwelt des Süsswassers'' (with Friedrich Blochmann, 1885/86) – The microscopic freshwater plant and animal world. * ''Die Krankheiten und Beschädigungen unserer landwirtschaftlichen Kulturpflanzen : eine Anleitung zu ihrer Erkennung und Bekämpfung ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Adhesive
Adhesive, also known as glue, cement, mucilage, or paste, is any non-metallic substance applied to one or both surfaces of two separate items that binds them together and resists their separation. The use of adhesives offers certain advantages over other binding techniques such as sewing, mechanical fastenings, or welding. These include the ability to bind different materials together, the more efficient distribution of stress across a joint, the cost-effectiveness of an easily mechanized process, and greater flexibility in design. Disadvantages of adhesive use include decreased stability at high temperatures, relative weakness in bonding large objects with a small bonding surface area, and greater difficulty in separating objects during testing. Adhesives are typically organized by the method of adhesion followed by ''reactive'' or ''non-reactive'', a term which refers to whether the adhesive chemically reacts in order to harden. Alternatively, they can be organized eit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydroxyquinol
Hydroxyquinol is an organic compound with the formula C6H3(OH)3. It is one of three isomeric benzenetriols. The compound is a colorless solid that is soluble in water. It reacts with air to give a black insoluble solid. Production It is prepared industrially by acetylation of paraquinone with acetic anhydride followed by hydrolysis of the triacetate. Historically hydroxyquinol was produced by the action of potassium hydroxide on hydroquinone. It can also be prepared by dehydrating fructose. :C6H12O6 → 3 H2O + C6H6O3 Natural occurrence Hydroxyquinol is a common intermediate in the biodegradation of many aromatic compounds. These substrates include monochlorophenols, dichlorophenols, and more complex species such as the pesticide 2,4,5-T. Hydroxyquinol commonly occurs in nature as a biodegradation product of catechin, a natural phenol found in plants (e.g. by soil bacteria '' Bradyrhizobium japonicum''). Hydroxyquinol is also a metabolite in some organisms. For insta ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Resorcinol
Resorcinol (or resorcin) is an organic compound with the formula C6H4(OH)2. It is one of three isomeric benzenediols, the 1,3-isomer (or '' meta''-isomer). Resorcinol crystallizes from benzene as colorless needles that are readily soluble in water, alcohol, and ether, but insoluble in chloroform and carbon disulfide. Production Resorcinol is produced in several steps from benzene, starting with dialkylation with propylene to give 1,3-diisopropylbenzene. Oxidation and Hock rearrangement of this disubstituted arene gives acetone and resorcinol. Resorcinol is an expensive chemical, produced in only a very few locations around the world (to date only four commercial plants are known to be operative: in the United States, Germany,China and Japan), and as such it is the determining factor in the cost of PRF adhesives. Many additional routes exist for resorcinol. It was formerly produced by disulfonation of benzene followed by hydrolysis of the 1,3-disulfonate. This method ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phloroglucinol
Phloroglucinol is an organic compound with the formula C6H3(OH)3. It is a colorless solid. It is used in the synthesis of pharmaceuticals and explosives. Phloroglucinol is one of three isomeric benzenetriols. The other two isomers are hydroxyquinol (1,2,4-benzenetriol) and pyrogallol (1,2,3-benzenetriol). Phloroglucinol, and its benzenetriol isomers, are still defined as "phenols" according to the IUPAC official nomenclature rules of chemical compounds. Many such monophenolics are often termed "polyphenols" by the cosmetic and parapharmaceutical industries, which does not match the scientifically accepted definition. Synthesis and occurrence In 1855, phloroglucinol was first prepared from phloretin by the Austrian chemist Heinrich Hlasiwetz (1825–1875). A modern synthesis of involves hydrolysis of benzene-1,3,5-triamine and its derivatives. Representative is the following route from trinitrobenzene. : The synthesis is noteworthy because ordinary aniline derivatives are ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phloroglucinol Carboxylic Acid
Phloroglucinol carboxylic acid is a trihydroxybenzoic acid, a type of phenolic acid. It is produced by ''Pseudomonas fluorescens''. It is a 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 ta ... degradation product excreted by the bacterium '' Acinetobacter calcoaceticus'', a species of bacteria part of the human body normal flora, grown on catechin as sole source of carbon. It is also found in wine.C. García Barroso, R. Cela Torrijos and J. A. Pérez-Bustamante: ''HPLC separation of benzoic and hydroxycinnamic acids in wines'', Chromatographia, Volume 17, Number 5, pages 249–252, . References Trihydroxybenzoic acids Phloroglucinols {{aromatic-stub ... [...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 chiral centers on the molecule on carbons 2 and 3. Therefore, it has four diastereoisomers. Two of the isomers are in trans configuration and are called ''catechin'' and the other two are in cis configuration and are called ''epicatechin''. The most common catechin isomer is (+)-catechin. The other stereoisomer is (-)-catechin or ''ent''-catechin. The most common epicatechin isomer is (-)-epic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Base Pairs
A base pair (bp) is a fundamental unit of double-stranded nucleic acids consisting of two nucleobases bound to each other by hydrogen bonds. They form the building blocks of the DNA double helix and contribute to the folded structure of both DNA and RNA. Dictated by specific hydrogen bonding patterns, "Watson–Crick" (or "Watson–Crick–Franklin") base pairs ( guanine– cytosine and adenine– thymine) allow the DNA helix to maintain a regular helical structure that is subtly dependent on its nucleotide sequence. The complementary nature of this based-paired structure provides a redundant copy of the genetic information encoded within each strand of DNA. The regular structure and data redundancy provided by the DNA double helix make DNA well suited to the storage of genetic information, while base-pairing between DNA and incoming nucleotides provides the mechanism through which DNA polymerase replicates DNA and RNA polymerase transcribes DNA into RNA. Many DNA-binding p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Circular Bacterial Chromosome
A circular chromosome is a chromosome in bacteria, archaea, mitochondria, and chloroplasts, in the form of a molecule of circular DNA, unlike the linear chromosome of most eukaryotes. Most prokaryote chromosomes contain a circular DNA molecule – there are no free ends to the DNA. Free ends would otherwise create significant challenges to cells with respect to DNA replication and stability. Cells that do contain chromosomes with DNA ends, or telomeres (most eukaryotes), have acquired elaborate mechanisms to overcome these challenges. However, a circular chromosome can provide other challenges for cells. After replication, the two progeny circular chromosomes can sometimes remain interlinked or tangled, and they must be resolved so that each cell inherits one complete copy of the chromosome during cell division. Replication The circular bacteria chromosome replication is best understood in the well-studied bacteria '' Escherichia coli'' and '' Bacillus subtilis''. Chrom ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Genome
In the fields of molecular biology and genetics, a genome is all the genetic information of an organism. It consists of nucleotide sequences of DNA (or RNA in RNA viruses). The nuclear genome includes protein-coding genes and non-coding genes, other functional regions of the genome such as regulatory sequences (see non-coding DNA), and often a substantial fraction of 'junk' DNA with no evident function. Almost all eukaryotes have mitochondria and a small mitochondrial genome. Algae and plants also contain chloroplasts with a chloroplast genome. The study of the genome is called genomics. The genomes of many organisms have been sequenced and various regions have been annotated. The International Human Genome Project reported the sequence of the genome for ''Homo sapiens'' in 200The Human Genome Project although the initial "finished" sequence was missing 8% of the genome consisting mostly of repetitive sequences. With advancements in technology that could handle seq ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Soybean
The soybean, soy bean, or soya bean (''Glycine max'') is a species of legume native to East Asia, widely grown for its edible bean, which has numerous uses. Traditional unfermented food uses of soybeans include soy milk, from which tofu and tofu skin are made. Fermented soy foods include soy sauce, fermented bean paste, nattō, and tempeh. Fat-free (defatted) soybean meal is a significant and cheap source of protein for animal feeds and many packaged meals. For example, soybean products, such as textured vegetable protein (TVP), are ingredients in many meat and dairy substitutes. Soybeans contain significant amounts of phytic acid, dietary minerals and B vitamins. Soy vegetable oil, used in food and industrial applications, is another product of processing the soybean crop. Soybean is the most important protein source for feed farm animals (that in turn yields animal protein for human consumption). Etymology The word "soy" originated as a corruption of the Cant ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plant Ecology
Plant ecology is a subdiscipline of ecology which studies the distribution and abundance of plants, the effects of environmental factors upon the abundance of plants, and the interactions among and between plants and other organisms. Examples of these are the distribution of temperate deciduous forests in North America, the effects of drought or flooding upon plant survival, and competition among desert plants for water, or effects of herds of grazing animals upon the composition of grasslands. A global overview of the Earth's major vegetation types is provided by O.W. Archibold. He recognizes 11 major vegetation types: tropical forests, tropical savannas, arid regions (deserts), Mediterranean ecosystems, temperate forest ecosystems, temperate grasslands, coniferous forests, tundra (both polar and high mountain), terrestrial wetlands, freshwater ecosystems and coastal/marine systems. This breadth of topics shows the complexity of plant ecology, since it includes plants fro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
