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Spermidine
Spermidine is a polyamine compound () found in ribosomes and living tissues and having various metabolic functions within organisms. Function Spermidine is an Aliphatic compound, aliphatic polyamine. Spermidine synthase (SPDS) catalyzes its formation from putrescine. It is a precursor to other polyamines, such as spermine and its structural isomer polyamine#thermospermine, thermospermine. Spermidine synchronizes an array of biological processes, (such as Ca2+, Na+, K+ -ATPase) thus maintaining membrane potential and controlling intracellular pH and volume. Spermidine regulates biological processes, such as Ca2+ influx by glutamatergic N-Methyl-D-aspartic acid, ''N''-methyl-D-aspartate receptor (NMDA receptor), which has been associated with nitric oxide synthase (NOS) and cGMP/PKG pathway activation and a decrease of Na+,K+-ATPase activity in cerebral cortex synaptosomes. Spermidine is a longevity agent in mammals due to various mechanisms of action, which are just beginning to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spermidine Synthase
Spermidine synthase is an enzyme () that catalyzes the transfer of the propylamine group from ''S''-adenosylmethioninamine to putrescine in the biosynthesis of spermidine. The systematic name is S-adenosyl 3-(methylthio)propylamine:putrescine 3-aminopropyltransferase and it belongs to the group of aminopropyl transferases. It does not need any cofactors. Most spermidine synthases exist in solution as dimers. Specificity With exception of the spermidine synthases from ''Thermotoga maritimum'' and from ''Escherichia coli'', which accept different kinds of polyamines, all enzymes are highly specific for putrescine. No known spermidine synthase can use ''S''-adenosyl methionine. This is prevented by a conserved aspartatyl residue in the active site, which is thought to repel the carboxyl moiety of ''S''-adenosyl methionine. The putrescine-N-methyl transferase whose substrates are putrescine and ''S''-adenosyl methionine, and which is evolutionary related to the spermidine syntha ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Putrescine
Putrescine is an organic compound with the formula (CH2)4(NH2)2. It is a colorless solid that melts near room temperature. It is classified as a diamine. Together with cadaverine, it is largely responsible for the foul odor of Putrefaction, putrefying flesh, but also contributes to other unpleasant odors. Production Putrescine is produced on an industrial scale by the hydrogenation of succinonitrile. Biotechnological production of putrescine from a renewable feedstock has been investigated. A metabolically engineered strain of ''Escherichia coli'' that produces putrescine at high concentrations in glucose mineral salts medium has been described. Biochemistry Spermidine synthase uses putrescine and S-Adenosylmethioninamine, ''S''-adenosylmethioninamine (decarboxylated S-Adenosyl methionine, ''S''-adenosyl methionine) to produce spermidine. Spermidine in turn is combined with another ''S''-adenosylmethioninamine and gets converted to spermine. Putrescine is synthesized in small q ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polyamine Synthesis
A polyamine is an organic compound having two or more amino groups. Alkyl polyamines occur naturally, but some are synthetic. Alkylpolyamines are colorless, hygroscopic, and water soluble. Near neutral pH, they exist as the ammonium derivatives. Most aromatic polyamines are crystalline solids at room temperature. Natural polyamines Low-molecular-weight linear polyamines are found in all forms of life. The principal examples are the triamine spermidine and the tetraamine spermine. They are structurally and biosynthetically related to the diamines putrescine and cadaverine. Polyamine metabolism is regulated by the activity of the enzyme ornithine decarboxylase (ODC). Polyamines are found in high concentrations in the mammalian brain. File:Spermidine-2D-skeletal.svg, spermidine File:Spermine.svg, spermine Synthetic polyamines Ethyleneamines are a commercially-important class of synthetic polyamines with ethylene ( linkages); global production capacity was estimated at 385,000 t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spermine
Spermine is a polyamine involved in cellular metabolism that is found in all eukaryotic cells. The precursor for synthesis of spermine is the amino acid ornithine. It is an essential growth factor in some bacteria as well. It is found as a polycation at physiological pH. Spermine is associated with nucleic acids and is thought to stabilize helical structure, particularly in viruses. It functions as an intracellular free radical scavenger to protect DNA from free radical attack. Spermine is the chemical primarily responsible for the characteristic odor of semen. Antonie van Leeuwenhoek first described crystals of spermine phosphate in human semen in 1678. The name ''spermin'' was first used by the German chemists Ladenburg and Abel in 1888, and the correct structure of spermine was not finally established until 1926, simultaneously in England (by Dudley, Rosenheim, and Starling) and Germany (by Wrede et al.). Derivative A derivative of spermine, N1, N12-bis(ethyl)sperm ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polyamine
A polyamine is an organic compound having two or more amino groups. Alkyl polyamines occur naturally, but some are synthetic. Alkylpolyamines are colorless, hygroscopic, and water soluble. Near neutral pH, they exist as the ammonium derivatives. Most aromatic polyamines are crystalline solids at room temperature. Natural polyamines Low-molecular-weight linear polyamines are found in all forms of life. The principal examples are the triamine spermidine and the tetraamine spermine. They are structurally and biosynthetically related to the diamines putrescine and cadaverine. Polyamine metabolism is regulated by the activity of the enzyme ornithine decarboxylase (ODC). Polyamines are found in high concentrations in the mammalian brain. File:Spermidine-2D-skeletal.svg, spermidine File:Spermine.svg, spermine Synthetic polyamines Ethyleneamines are a commercially-important class of synthetic polyamines with ethylene ( linkages); global production capacity was estimated at 385,00 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Methyl-n-amylnitrosamine
Methyl-''n''-amylnitrosamine (MNAN) is a potential carcinogen It is metabolized in the liver by the enzyme CYP2A6 Cytochrome P450 2A6 (abbreviated CYP2A6) is a member of the cytochrome P450 mixed-function oxidase system, which is involved in the metabolism of xenobiotics in the body. CYP2A6 is the primary enzyme responsible for the oxidation of nicotine an .... References Carcinogens Nitrosamines {{organic-compound-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dipropylamine
Dipropylamine is an organic compound with the formula . It is classified as a secondary amine. It is a colorless liquid with a "fishy" odor. It is a precursor to various herbicides such as trifluralin, oryzalin, and vernolate. : left, Trifluralin, an herbicide containing a dipropylamino group, 110px Occurrence Dipropylamine occurs in tobacco leaves and in some industrial wastes. Safety Dipropylamine is flammable, toxic, and corrosive. Exposure can cause excitement followed by depression, internal bleeding, dystrophy Dystrophy is the degeneration of tissue, due to disease or malnutrition, most likely due to heredity. Types * Muscular dystrophy ** Duchenne muscular dystrophy ** Becker's muscular dystrophy ** Myotonic dystrophy * Reflex neurovascular dy ..., and severe irritation. References {{reflist Alkylamines Dipropylamino compounds Secondary amines ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dibutylamine
Dibutylamine is a colorless fluid with a fishy odor. It is an amine used as a corrosion inhibitor, in the manufacturing of emulsifiers, and as a flotation agent. It is flammable and toxic Toxicity is the degree to which a chemical substance or a particular mixture of substances can damage an organism. Toxicity can refer to the effect on a whole organism, such as an animal, bacterium, or plant, as well as the effect on a subst .... References Alkylamines Corrosion inhibitors Dibutylamino compounds Secondary amines {{amine-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Norspermidine
Norspermidine is a polyamine of similar structure to the more common spermidine Spermidine is a polyamine compound () found in ribosomes and living tissues and having various metabolic functions within organisms. Function Spermidine is an Aliphatic compound, aliphatic polyamine. Spermidine synthase (SPDS) catalyzes its form .... While norspermidine has been found to occur naturally in some species of plants, bacteria, and algae, it is not known to exist in humans. Norspermidine is being researched for use as a cancer medication. References {{reflist 1,3-Propanediyl compounds Polyamines Secondary amines ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wheat Germ
The germ of a cereal grain is the part that develops into a plant; it is the seed embryo. Along with bran, germ is often a by-product of the milling that produces refined grain products. Cereal grains and their components, such as wheat germ oil, rice bran oil, and maize bran, may be used as a source from which vegetable oil is extracted, or used directly as a food ingredient. The germ is retained as an integral part of whole-grain foods. Non-whole grain methods of milling are intended to isolate the endosperm, which is ground into flour, with removal of both the husk (bran) and the germ. Removal of bran produces a flour with a white rather than a brown color and eliminates fiber. The germ is rich in polyunsaturated fats (which have a tendency to oxidize and become rancid on storage) and so germ removal improves the storage qualities of flour. Wheat germ Wheat germ or wheatgerm is a concentrated source of several essential nutrients, including vitamin E, folate (folic acid ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Electroporation
Electroporation, also known as electropermeabilization, is a microbiological and biotechnological technique in which an electric field is applied to cells to briefly increase the permeability of the cell membrane. The application of a high-voltage electric field induces a temporary destabilization of the lipid bilayer, resulting in the formation of nanoscale pores that permit the entry or exit of macromolecules. This method is widely employed to introduce molecules—including small molecules, DNA, RNA, and proteins—into cells. Electroporation can be performed on cells in suspension using electroporation cuvettes, or directly on adherent cells ''in situ'' within their culture vessels. In microbiology, electroporation is frequently utilized for the transformation of bacteria or yeast cells, often with plasmid DNA. It is also used in the transfection of plant protoplasts and mammalian cells. Notably, electroporation plays a critical role in the '' ex vivo'' manipulation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
