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Paxilline
Paxilline is a toxic, tremorgenic diterpene indole polycyclic alkaloid molecule produced by '' Penicillium paxilli ''which was first characterized in 1975. Paxilline is one of a class of tremorigenic mycotoxins, is a potassium channel blocker, and is potentially genotoxic. Paxilline was found to significantly extend the lifespan, healthspan, and mobility of aged '' C. elegans'' worms, but had no such effect on young worms. Paxilline was not found to induce seizures when injected intracerebroventricularly in mice but paradoxically had anticonvulsant activity against picrotoxin and pentylenetetrazol seizures in mice. It has also been used in mice to induce autism-like behaviors through inhibition of the BK channel. Biosynthesis Paxiline biosynthesis starts with the synthesis of geranylgeranyl pyrophosphate via the terpenoid pathway and indole-3-glycerol phosphate, which is an intermediate in the tryptophan biosynthesis pathway. By expressing six genes known to be necessary ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paxillin
Paxillin is a protein that in humans is encoded by the ''PXN'' gene. Paxillin is expressed at focal adhesions of non-striated cells and at costameres of striated muscle cells, and it functions to adhere cells to the extracellular matrix. Mutations in ''PXN'' as well as abnormal expression of paxillin protein has been implicated in the progression of various cancers. Structure Human paxillin is 64.5 kDa in molecular weight and 591 amino acids in length. The C-terminal region of paxillin is composed of four tandem double zinc finger LIM domains that are cysteine/histidine-rich with conserved repeats; these serve as binding sites for the protein tyrosine phosphatase-PEST, tubulin and serves as the targeting motif for focal adhesions. The N-terminal region of paxillin has five highly conserved leucine-rich sequences termed LD motifs, which mediate several interactions, including that with pp125FAK and vinculin. The LD motifs are predicted to form amphipathic alpha helices, w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Penicillium Paxilli
''Penicillium paxilli'' is an anamorph, saprophytic species of the genus ''Penicillium'' which produces paxilline Paxilline is a toxic, tremorgenic diterpene indole polycyclic alkaloid molecule produced by '' Penicillium paxilli ''which was first characterized in 1975. Paxilline is one of a class of tremorigenic mycotoxins, is a potassium channel blocker, ..., paxisterol, , pyrenocine A, paspaline B and verruculogene. ''Penicillium paxilli'' is used as a model to study the biochemistry of the indole-diterepene biosynthesis Further reading * * * * * * * * * * * * * * * References {{Taxonbar, from=Q10623024 paxilli Fungi described in 1907 Fungus species ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aspergillus Oryzae
''Aspergillus oryzae'', also known as , is a mold used in East Asia to saccharify rice, sweet potato, and barley in the making of alcoholic beverages such as '' sake'' and '' shōchū'', and also to ferment soybeans for making soy sauce and '' miso''. It is one of the different koji molds used for food fermentation. However, in the production of fermented foods of soybeans such as soy sauce and ''miso'', '' Aspergillus sojae'' is sometimes used instead of ''A. oryzae''. ''A. oryzae'' is also used for the production of rice vinegars. Barley ''kōji'' (麦麹) or rice ''kōji'' (米麹) are made by fermenting the grains with ''A. oryzae'' hyphae. The technique of solid-state cultivation using rice grains, soybeans, and wheat bran to propagate fungi for use in fermented foods is believed to have originated in China. However, there are two scholarly theories regarding the country that first employed ''A. oryzae'' in the production of fermented foods: one suggests it was China, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geranylgeranyl Pyrophosphate
Geranylgeranyl pyrophosphate is an intermediate in the biosynthesis of diterpenes and diterpenoids. It is also the precursor to carotenoids, gibberellins, tocopherols, and chlorophylls. It is also a precursor to geranylgeranylated proteins, which is its primary use in human cells. It is formed from farnesyl pyrophosphate by the addition of an isoprene unit from isopentenyl pyrophosphate. In ''Drosophila'', geranylgeranyl pyrophosphate is synthesised by HMG-CoA encoded by the Columbus gene. Geranylgeranyl pyrophosphate is utilised as a chemoattractant for migrating germ cells that have traversed the midgut epithelia. The attractant signal is produced at the gonadal precursors, directing the germ cells to these sites, where they will differentiate into eggs and spermatozoa (sperm). Related compounds * Farnesyl pyrophosphate * Geranylgeraniol Geranylgeraniol is a diterpenoid alcohol. It is a colorless waxy solid. It is an important intermediate in the biosynthesis of other ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ketones
In organic chemistry, a ketone is an organic compound with the structure , where R and R' can be a variety of carbon-containing substituents. Ketones contain a carbonyl group (a carbon-oxygen double bond C=O). The simplest ketone is acetone (where R and R' are methyl), with the formula . Many ketones are of great importance in biology and industry. Examples include many sugars (ketoses), many steroids, ''e.g.'', testosterone, and the solvent acetone. Nomenclature and etymology The word ''ketone'' is derived from ''Aketon'', an old German word for ''acetone''. According to the rules of IUPAC nomenclature, ketone names are derived by changing the suffix ''-ane'' of the parent alkane to ''-anone''. Typically, the position of the carbonyl group is denoted by a number, but traditional nonsystematic names are still generally used for the most important ketones, for example acetone and benzophenone. These nonsystematic names are considered retained IUPAC names, although some introd ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tertiary Alcohols
In chemistry, an alcohol (), is a type of organic compound that carries at least one hydroxyl () functional group bound to a Saturated and unsaturated compounds, saturated carbon atom. Alcohols range from the simple, like methanol and ethanol, to complex, like sugar alcohols and cholesterol. The presence of an OH group strongly modifies the properties of Hydrocarbon, hydrocarbons, conferring Hydrophile, hydrophilic (water-loving) properties. The OH group provides a site at which many reactions can occur. History The flammable nature of the exhalations of wine was already known to ancient natural philosophers such as Aristotle (384–322 BCE), Theophrastus (–287 BCE), and Pliny the Elder (23/24–79 CE). However, this did not immediately lead to the isolation of alcohol, even despite the development of more advanced distillation techniques in second- and third-century Roman Egypt. An important recognition, first found in one of the writings attributed to Jabir ibn Hayyan, J� ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Indole Alkaloids
Indole alkaloids are a class of alkaloids containing a Moiety (chemistry), structural moiety of indole; many indole alkaloids also include isoprene groups and are thus called terpene indole or secologanin tryptamine alkaloids. Containing more than 4100 known different compounds, it is one of the largest classes of alkaloids. Many of them possess significant physiological activity and some of them are used in medicine. The amino acid tryptophan is the biochemical precursor of indole alkaloids. History The action of some indole alkaloids has been known for ages. Aztecs used the psilocybin mushrooms which contain alkaloids psilocybin and psilocin. The flowering plant ''Rauvolfia serpentina'' which contains reserpine was a common medicine in India around 1000 BC. Africans used the roots of the perennial rainforest shrub Tabernanthe iboga, Iboga, which contain ibogaine, as a stimulant. An infusion of Calabar bean seeds was given to people accused of crime in Nigeria: its rejection by s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dimethylallyl Pyrophosphate
Dimethylallyl pyrophosphate (DMAPP; or alternatively, dimethylallyl diphosphate (DMADP); also isoprenyl pyrophosphate) is an isoprenoid precursor. It is a product of both the mevalonate pathway and the MEP pathway of isoprenoid precursor biosynthesis. It is an isomer of isopentenyl pyrophosphate (IPP) and exists in virtually all life forms. The enzyme isopentenyl pyrophosphate isomerase catalyzes isomerization between DMAPP and IPP. In the mevalonate pathway, DMAPP is synthesised from mevalonic acid. In contrast, DMAPP is synthesised from HMBPP in the MEP pathway. At present, it is believed that there is crossover between the two pathways in organisms that use both pathways to create terpenes and terpenoid The terpenoids, also known as isoprenoids, are a class of naturally occurring organic compound, organic chemicals derived from the 5-carbon compound isoprene and its derivatives called terpenes, diterpenes, etc. While sometimes used interchangeabl ...s, such as in plant ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Prenylation
Prenylation (also known as isoprenylation or lipidation) is the addition of hydrophobic molecules to a protein or a biomolecule. It is usually assumed that prenyl groups (3-methylbut-2-en-1-yl) facilitate attachment to cell membranes, similar to lipid anchors like the GPI anchor, though direct evidence of this has not been observed. Prenyl groups (also called isoprenyl groups, having one hydrogen atom more than isoprene) have been shown to be important for protein–protein binding through specialized prenyl-binding domains. Protein prenylation Protein prenylation involves the transfer of either a farnesyl or a geranylgeranyl moiety to C-terminal cysteine(s) of the target protein. There are three enzymes that carry out prenylation in the cell, farnesyl transferase, Caax protease and geranylgeranyl transferase I. Farnesylation is a type of prenylation, a post-translational modification of proteins by which an isoprenyl group is added to a cysteine residue. It is an important ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Epoxide
In organic chemistry, an epoxide is a cyclic ether, where the ether forms a three-atom ring: two atoms of carbon and one atom of oxygen. This triangular structure has substantial ring strain, making epoxides highly reactive, more so than other ethers. They are produced on a large scale for many applications. In general, low molecular weight epoxides are colourless and nonpolar, and often volatile. Nomenclature A compound containing the epoxide functional group can be called an epoxy, epoxide, oxirane, and ethoxyline. Simple epoxides are often referred to as oxides. Thus, the epoxide of ethylene (C2H4) is ethylene oxide (C2H4O). Many compounds have trivial names; for instance, ethylene oxide is called "oxirane". Some names emphasize the presence of the epoxide functional group, as in the compound ''1,2-epoxyheptane'', which can also be called ''1,2-heptene oxide''. A polymer formed from epoxide precursors is called an ''epoxy''. However, few if any of the epoxy groups i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
