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4-(γ-Glutamylamino)butanoic Acid
4-(γ-Glutamylamino)butanoic acid is molecule that consists of L-glutamate conjugated to γ-aminobutyric acid (GABA). It is the substrate of the enzyme γ-glutamyl-γ-aminobutyrate hydrolase, which is involved in the biosynthesis of polyamine A polyamine is an organic compound having more than two 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. ...s. References Amino acid derivatives Biosynthesis Dicarboxylic acids {{biochem-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hopantenic Acid
Hopantenic acid (homopantothenic acid), also known as N-pantoyl-GABA, is a central nervous system depressant. Formulated as the calcium salt, it is used as a pharmaceutical drug in the Russian Federation for a variety of neurological, psychological and psychiatric conditions and sold as Pantogam (russian: Пантогам). It is not approved for use in Europe or the United States. Chemistry Hopantenic acid is a homologue of pantothenic acid. While pantothenic acid is the amide of D-pantoate and β-alanine, hopantenic acid is the amide of D-pantoate and γ-aminobutyric acid (GABA). This change leads to an additional CH2 in the molecule. See also * Methyl pentanoate * Menthyl isovalerate Menthyl isovalerate, also known as validolum, is the menthyl ester of isovaleric acid. It is a transparent oily, colorless liquid with a smell of menthol. It is very slightly soluble in ethanol, while practically insoluble in water. It is used a ... References External links pantogab ( ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hypusine
Hypusine is an uncommon amino acid found in all eukaryotes and in some archaea, but not in bacteria. The only known proteins containing the hypusine residue is eukaryotic translation initiation factor 5A (eIF-5A) and a similar protein found in archaea. In humans, two isoforms of eIF-5A have been described: eIF5A-1 and eIF5A-2. They are encoded by two distinct genes EIF5A and EIF5A2. The protein is involved in protein biosynthesis and promotes the formation of the first peptide bond. The region surrounding the hypusine residue is highly conserved and is essential to the function of eIF5A. Thus, hypusine and eIF-5A appear to be vital for the viability and proliferation of eukaryotic cells. Hypusine is formed in eIF-5A by post-translational modification of one of the lysyl residues. Two reactions and two enzymes are involved: *1. Deoxyhypusine synthase catalyzes the cleavage of the polyamine spermidine and transfer of its 4-aminobutyl moiety to the ε-amino group of one specif ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Saccharopine
Saccharopine is an intermediate in the metabolism of amino acid lysine. It is a precursor of lysine in the alpha-aminoadipate pathway which occurs in fungi and euglenids. In mammals and higher plants saccharopine is an intermediate in the degradation of lysine, formed by condensation of lysine and alpha-ketoglutarate. Reaction The reactions involved, catalysed by saccharopine dehydrogenases, are: :lysine + alpha-ketoglutarate ⇌ saccharopine ⇌ glutamate + 2-aminoadipate 6-semialdehyde Pathology Saccharopinuria (high amounts of saccharopine in the urine) and saccharopinemia (an excess of saccharopine in the blood) are conditions present in some inherited disorders of lysine degradation. History Saccharopine was first isolated in 1961 from yeasts (''Saccharomyces'', hence the name) by Darling and Larsen.Darling, S., and Larsen, P. O., Saccharopine, a new amino acid in Baker's and Brewer's yeast: I. Isolation and properties. ''Acta Chem. Scand.'', 15, 743 (1961). See also * ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glutamic Acid
Glutamic acid (symbol Glu or E; the ionic form is known as glutamate) is an α-amino acid that is used by almost all living beings in the biosynthesis of proteins. It is a non-essential nutrient for humans, meaning that the human body can synthesize enough for its use. It is also the most abundant excitatory neurotransmitter in the vertebrate nervous system. It serves as the precursor for the synthesis of the inhibitory gamma-aminobutyric acid (GABA) in GABA-ergic neurons. Its molecular formula is . Glutamic acid exists in three optically isomeric forms; the dextrorotatory -form is usually obtained by hydrolysis of gluten or from the waste waters of beet-sugar manufacture or by fermentation.Webster's Third New International Dictionary of the English Language Unabridged, Third Edition, 1971. Its molecular structure could be idealized as HOOC−CH()−()2−COOH, with two carboxyl groups −COOH and one amino group −. However, in the solid state and mildly acidic water solutio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Enzyme
Enzymes () are proteins that act as biological catalysts by accelerating chemical reactions. The molecules upon which enzymes may act are called substrates, and the enzyme converts the substrates into different molecules known as products. Almost all metabolic processes in the cell need enzyme catalysis in order to occur at rates fast enough to sustain life. Metabolic pathways depend upon enzymes to catalyze individual steps. The study of enzymes is called ''enzymology'' and the field of pseudoenzyme analysis recognizes that during evolution, some enzymes have lost the ability to carry out biological catalysis, which is often reflected in their amino acid sequences and unusual 'pseudocatalytic' properties. Enzymes are known to catalyze more than 5,000 biochemical reaction types. Other biocatalysts are catalytic RNA molecules, called ribozymes. Enzymes' specificity comes from their unique three-dimensional structures. Like all catalysts, enzymes increase the reaction ra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gamma-glutamyl-gamma-aminobutyrate Hydrolase
In enzymology, a gamma-glutamyl-gamma-aminobutyrate hydrolase () is an enzyme that catalyzes the chemical reaction : 4-(gamma-glutamylamino)butanoate + H2O \rightleftharpoons 4-aminobutanoate + L-glutamate Thus, the two substrates of this enzyme are 4-(gamma-glutamylamino)butanoate and H2O, whereas its two products are 4-aminobutanoate and L-glutamate. This enzyme belongs to the family of hydrolases, those acting on carbon-nitrogen bonds other than peptide bonds, specifically in linear amides. The systematic name of this enzyme class is 4-(gamma-glutamylamino)butanoate amidohydrolase. Other names in common use include gamma-glutamyl-GABA hydrolase, PuuD, and YcjL. This enzyme participates in urea cycle and metabolism of amino groups The urea cycle (also known as the ornithine cycle) is a cycle of biochemical reactions that produces urea (NH2)2CO from ammonia (NH3). Animals that use this cycle, mainly amphibians and mammals, are called ureotelic. The urea cycle conver ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polyamine
A polyamine is an organic compound having more than two 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 Several synthetic polyamines are used in chemical industry and the research laboratory. They are mainly of interest as additives to motor oil and as co-rea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Amino Acid Derivatives
In chemistry, amines (, ) are compounds and functional groups that contain a basic nitrogen atom with a lone pair. Amines are formally derivatives of ammonia (), wherein one or more hydrogen atoms have been replaced by a substituent such as an alkyl or aryl group (these may respectively be called alkylamines and arylamines; amines in which both types of substituent are attached to one nitrogen atom may be called alkylarylamines). Important amines include amino acids, biogenic amines, trimethylamine, and aniline; Inorganic derivatives of ammonia are also called amines, such as monochloramine (). The substituent is called an amino group. Compounds with a nitrogen atom attached to a carbonyl group, thus having the structure , are called amides and have different chemical properties from amines. Classification of amines Amines can be classified according to the nature and number of substituents on nitrogen. Aliphatic amines contain only H and alkyl substituents. Aromatic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Biosynthesis
Biosynthesis is a multi-step, enzyme-catalyzed process where substrates are converted into more complex products in living organisms. In biosynthesis, simple compounds are modified, converted into other compounds, or joined to form macromolecules. This process often consists of metabolic pathways. Some of these biosynthetic pathways are located within a single cellular organelle, while others involve enzymes that are located within multiple cellular organelles. Examples of these biosynthetic pathways include the production of lipid membrane components and nucleotides. Biosynthesis is usually synonymous with anabolism. The prerequisite elements for biosynthesis include: precursor compounds, chemical energy (e.g. ATP), and catalytic enzymes which may require coenzymes (e.g.NADH, NADPH). These elements create monomers, the building blocks for macromolecules. Some important biological macromolecules include: proteins, which are composed of amino acid monomers joined via peptide bon ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
