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Opines
Opines are low molecular weight compounds found in plant crown gall tumors or hairy root tumors produced by pathogenic bacteria of the genus ''Agrobacterium'' and ''Rhizobium''. Opine biosynthesis is catalyzed by specific enzymes encoded by genes contained in a small segment of DNA (known as the T-DNA, for 'transfer DNA'), which is part of the Ti plasmid (in ''Agrobacterium'') or Ri plasmid (in ''Rhizobium''), inserted by the bacterium into the plant genome. The opines are used by the bacterium as an important energy, carbon and nitrogen source. Each strain of ''Agrobacterium'' and ''Rhizobium'' induces and catabolizes a specific set of opines, this set typifying the Ti plasmid and Ri plasmid. There are some 30 different opines described so far. Chemical structure Chemically, opines fall into two major structural classes: 1. The vast majority are secondary amine derivatives resulting from the reduction of the imine formed by condensation of an amino acid, either with a ke ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ti Plasmid
A tumour inducing (Ti) plasmid is a plasmid found in pathogenic species of ''Agrobacterium'', including ''A. tumefaciens, ''A. rhizogenes'', ''A. rubi'' and ''A. vitis''. Evolutionarily, the Ti plasmid is part of a family of plasmids carried by many species of Alphaproteobacteria. Members of this plasmid family are defined by the presence of a conserved DNA region known as the ''repABC'' gene cassette, which mediates the replication of the plasmid, the partitioning of the plasmid into daughter cells during cell division as well as the maintenance of the plasmid at low copy numbers in a cell. The Ti plasmids themselves are sorted into different categories based on the type of molecule, or opine, they allow the bacteria to break down as an energy source. The presence of this Ti plasmid is essential for the bacteria to cause crown gall disease in plants. This is facilitated via certain crucial regions in the Ti plasmid, including the ''vir'' region, which encodes for virulence g ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nopaline
Nopaline is a chemical compound derived from the amino acids glutamic acid and arginine. It is classified as an opine. Ti plasmids are classified on the basis of the different types of opines they produce. These may be nopaline plasmids, octopine plasmids and agropine plasmids. These opines are condensation products of amino acids and keto acids or may be derived from sugars. The opines are used as carbon and nitrogen sources and metabolized by ''Agrobacterium ''Agrobacterium'' is a genus of Gram-negative bacteria established by H. J. Conn that uses horizontal gene transfer to cause tumors in plants. '' Agrobacterium tumefaciens'' is the most commonly studied species in this genus. ''Agrobacterium'' i ...''. References Amino acid derivatives {{organic-compound-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crown Gall
''Agrobacterium'' is a genus of Gram-negative bacteria established by H. J. Conn that uses horizontal gene transfer to cause tumors in plants. ''Agrobacterium tumefaciens'' is the most commonly studied species in this genus. ''Agrobacterium'' is well known for its ability to transfer DNA between itself and plants, and for this reason it has become an important tool for genetic engineering. Nomenclatural History Leading up to the 1990s, the genus ''Agrobacterium'' was used as a wastebasket taxon. With the advent of 16S sequencing, many ''Agrobacterium'' species (especially the marine species) were reassigned to genera such as ''Ahrensia'', ''Pseudorhodobacter'', ''Ruegeria'', and ''Stappia''. The remaining ''Agrobacterium'' species were assigned to three biovars: biovar 1 (''Agrobacterium tumefaciens''), biovar 2 (''Agrobacterium rhizogenes''), and biovar 3 (''Agrobacterium vitis''). In the early 2000s, ''Agrobacterium'' was synonymized with the genus ''Rhizobium''. This move pr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hairy Root Culture
Hairy root culture, also called transformed root culture, is a type of plant tissue culture that is used to study plant metabolic processes or to produce valuable secondary metabolites or recombinant proteins, often with plant genetic engineering. A naturally occurring soil bacterium ''Agrobacterium rhizogenes'' that contains root-inducing plasmids (also called Ri plasmids) can infect plant roots and cause them to produce a food source for the bacterium, opines, and to grow abnormally. The abnormal roots are particularly easy to culture in artificial media because hormones are not needed in contrast to adventitious roots, and they are neoplastic, with indefinite growth. The neoplastic roots produced by ''A. rhizogenes'' infection have a high growth rate (compared to untransformed adventitious roots), as well as genetic and biochemical stability. Currently the main constraint for commercial utilization of hairy root culture is the development and up-scaling of appropriate (bioreacto ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Octopine Structure
Octopine is a derivative of the amino acids arginine and alanine. It was the first member of the class of chemical compounds known as opines to be discovered. Octopine gets its name from '' Octopus octopodia'' from which it was first isolated in 1927. Octopine has been isolated from the muscle tissue of invertebrates such as octopus, ''Pecten maximus'' and ''Sipunculus nudus'' where it functions as an analog of lactic acid. Plants may also produce this compound after infection by '' Agrobacterium tumifaciens'' and transfer of the octopine synthesis gene from the bacterium to the plant. Octopine is formed by reductive condensation of pyruvic acid and arginine through the action of the NADH Nicotinamide adenine dinucleotide (NAD) is a coenzyme central to metabolism. Found in all living cells, NAD is called a dinucleotide because it consists of two nucleotides joined through their phosphate groups. One nucleotide contains an aden ...-dependent enzyme octopine dehydrogena ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Octopine
Octopine is a derivative of the amino acids arginine and alanine. It was the first member of the class of chemical compounds known as opines to be discovered. Octopine gets its name from '' Octopus octopodia'' from which it was first isolated in 1927. Octopine has been isolated from the muscle tissue of invertebrates such as octopus, ''Pecten maximus'' and ''Sipunculus nudus'' where it functions as an analog of lactic acid. Plants may also produce this compound after infection by '' Agrobacterium tumifaciens'' and transfer of the octopine synthesis gene from the bacterium to the plant. Octopine is formed by reductive condensation of pyruvic acid and arginine through the action of the NADH Nicotinamide adenine dinucleotide (NAD) is a coenzyme central to metabolism. Found in all living cells, NAD is called a dinucleotide because it consists of two nucleotides joined through their phosphate groups. One nucleotide contains an aden ...-dependent enzyme octopine dehydrogen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Agrobacterium
''Agrobacterium'' is a genus of Gram-negative bacteria established by H. J. Conn that uses horizontal gene transfer to cause tumors in plants. ''Agrobacterium tumefaciens'' is the most commonly studied species in this genus. ''Agrobacterium'' is well known for its ability to transfer DNA between itself and plants, and for this reason it has become an important tool for genetic engineering. Nomenclatural History Leading up to the 1990s, the genus ''Agrobacterium'' was used as a wastebasket taxon. With the advent of 16S sequencing, many ''Agrobacterium'' species (especially the marine species) were reassigned to genera such as ''Ahrensia'', ''Pseudorhodobacter'', ''Ruegeria'', and ''Stappia''. The remaining ''Agrobacterium'' species were assigned to three biovars: biovar 1 (''Agrobacterium tumefaciens''), biovar 2 (''Agrobacterium rhizogenes''), and biovar 3 (''Agrobacterium vitis''). In the early 2000s, ''Agrobacterium'' was synonymized with the genus ''Rhizobium''. This move pr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stylopine
Tetrahydrocoptisine (also known as stylopine) is an alkaloid isolated from ''Corydalis impatiens ''Corydalis'' (from Greek ''korydalís'' "crested lark") is a genus of about 470 species of annual and perennial herbaceous plants in the family Papaveraceae, native to the temperate Northern Hemisphere and the high mountains of tropical easte ...''. References {{reflist 5,6,7,8-Tetrahydro-(1,3)dioxolo(4,5-g)isoquinolines ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Atropine
Atropine is a tropane alkaloid and anticholinergic medication used to treat certain types of nerve agent and pesticide poisonings as well as some types of slow heart rate, and to decrease saliva production during surgery. It is typically given intravenously or by injection into a muscle. Eye drops are also available which are used to treat uveitis and early amblyopia. The intravenous solution usually begins working within a minute and lasts half an hour to an hour. Large doses may be required to treat some poisonings. Common side effects include a dry mouth, large pupils, urinary retention, constipation, and a fast heart rate. It should generally not be used in people with angle closure glaucoma. While there is no evidence that its use during pregnancy causes birth defects, that has not been well studied. It is likely safe during breastfeeding. It is an antimuscarinic (a type of anticholinergic) that works by inhibiting the parasympathetic nervous system. Atropine occurs n ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oxford English Dictionary
The ''Oxford English Dictionary'' (''OED'') is the first and foundational historical dictionary of the English language, published by Oxford University Press (OUP). It traces the historical development of the English language, providing a comprehensive resource to scholars and academic researchers, as well as describing usage in its many variations throughout the world. Work began on the dictionary in 1857, but it was only in 1884 that it began to be published in unbound fascicles as work continued on the project, under the name of ''A New English Dictionary on Historical Principles; Founded Mainly on the Materials Collected by The Philological Society''. In 1895, the title ''The Oxford English Dictionary'' was first used unofficially on the covers of the series, and in 1928 the full dictionary was republished in 10 bound volumes. In 1933, the title ''The Oxford English Dictionary'' fully replaced the former name in all occurrences in its reprinting as 12 volumes with a one-v ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
