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Aspartoacylase
Aspartoacylase is a hydrolytic enzyme (, also called aminoacylase II, ASPA and other names) that in humans is encoded by the ''ASPA'' gene. ASPA catalyzes the deacylation of ''N''-acetyl-l-aspartate (''N-acetylaspartate)'' into aspartate and acetate. It is a zinc-dependent hydrolase that promotes the deprotonation of water to use as a nucleophile in a mechanism analogous to many other zinc-dependent hydrolases. It is most commonly found in the brain, where it controls the levels of ''N''-acetyl-l-aspartate. Mutations that result in loss of aspartoacylase activity are associated with Canavan disease, a rare autosomal recessive neurodegenerative disease. Structure Aspartoacylase is a dimer of two identical monomers of 313 amino acids and uses a zinc cofactor in each. There are two distinct domains in each monomer: the N-terminal domain from residues 1-212 and the C-terminal domain from residues 213–313. The N-terminal domain of aspartoacylase is similar to that of zinc- ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ASPA Mechanism
ASPA may refer to: *''Allocation de Solidarité aux Personnes Agées'' *American Service-Members' Protection Act *American Society for Public Administration *American Samoa Power Authority *Animals (Scientific Procedures) Act 1986 *Antarctic Specially Protected Area *Aotearoa Student Press Association * ASPA (car), a 1920s Czech car *ASPA (gene) Aspartoacylase is a hydrolytic enzyme (, also called aminoacylase II, ASPA and other names) that in humans is encoded by the ''ASPA'' gene. ASPA catalyzes the deacylation of ''N''-acetyl-l-aspartate (''N-acetylaspartate)'' into aspartate and ..., Aspartoacylase, on human chromosome 17 * in Internet routing * Summit of South American-Arab Countries See also * Aspa (other) {{Disambiguation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
N-Acetylaspartate
''N''-Acetylaspartic acid, or ''N''-acetylaspartate (NAA), is a derivative of aspartic acid with a formula of C6H9NO5 and a molecular weight of 175.139. NAA is the second-most-concentrated molecule in the brain after the amino acid glutamate. It is detected in the adult brain in neurons, oligodendrocytes and myelin and is synthesized in the Mitochondrion, mitochondria from the amino acid aspartic acid and Acetyl-CoA, acetyl-coenzyme A. Function The various functions served by NAA are under investigation, but the primary proposed functions include: * Neuronal osmolyte that is involved in fluid balance in the brain * Source of acetate for lipid and myelin synthesis in oligodendrocytes, the Neuroglia, glial cells that myelinate neuronal axons * Precursor for the synthesis of the neuronal dipeptide N-Acetylaspartylglutamate * Contributor to energy production from the amino acid glutamate in neuronal mitochondria. In the brain, NAA was thought to be present predominantly in neu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ASPA Bound To An Intermediate Analogue
ASPA may refer to: *''Allocation de Solidarité aux Personnes Agées'' *American Service-Members' Protection Act *American Society for Public Administration *American Samoa Power Authority *Animals (Scientific Procedures) Act 1986 *Antarctic Specially Protected Area *Aotearoa Student Press Association * ASPA (car), a 1920s Czech car *ASPA (gene) Aspartoacylase is a hydrolytic enzyme (, also called aminoacylase II, ASPA and other names) that in humans is encoded by the ''ASPA'' gene. ASPA catalyzes the deacylation of ''N''-acetyl-l-aspartate (''N-acetylaspartate)'' into aspartate and ..., Aspartoacylase, on human chromosome 17 * in Internet routing * Summit of South American-Arab Countries See also * Aspa (other) {{Disambiguation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydrolase
In biochemistry, hydrolases constitute a class of enzymes that commonly function as biochemical catalysts that use water to break a chemical bond: :\ce \quad \xrightarrowtext\quad \ce This typically results in dividing a larger molecule into smaller molecules. Some common examples of hydrolase enzymes are esterases including lipases, phosphatases, glycosidases, peptidases, and nucleosidases. Esterases cleave ester bonds in lipids and phosphatases cleave phosphate groups off molecules. An example of crucial esterase is acetylcholine esterase, which assists in transforming the neuron impulse into the acetate group after the hydrolase breaks the acetylcholine into choline and acetic acid. Acetic acid is an important metabolite in the body and a critical intermediate for other reactions such as glycolysis. Lipases hydrolyze glycerides. Glycosidases cleave sugar molecules off carbohydrates and peptidases hydrolyze peptide bonds. Nucleosidases hydrolyze the bonds of nucleo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carboxypeptidase A
Carboxypeptidase A usually refers to the pancreatic exopeptidase that hydrolyzes peptide bonds of C-terminal residues with aromatic or aliphatic Side chain, side-chains. Most scientists in the field now refer to this enzyme as CPA1, and to a related pancreatic carboxypeptidase as CPA2. Types In addition, there are 4 other mammalian enzymes named CPA-3 through CPA-6, and none of these are expressed in the pancreas. Instead, these other CPA-like enzymes have diverse functions. * CPA3 (also known as mast-cell CPA) is involved in the digestion of proteins by mast cells. * CPA4 (gene), CPA4 (previously known as CPA-3, but renumbered when mast-cell CPA was designated CPA-3) may be involved in tumor progression, but this enzyme has not been well studied. * CPA5 has not been well studied. * CPA6 is expressed in many tissues during mouse development, and in adult shows a more limited distribution in brain and several other tissues. CPA6 is present in the extracellular matrix where it i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carbonyl
In organic chemistry, a carbonyl group is a functional group with the formula , composed of a carbon atom double bond, double-bonded to an oxygen atom, and it is divalent at the C atom. It is common to several classes of organic compounds (such as aldehydes, ketones and carboxylic acid), as part of many larger functional groups. A compound containing a carbonyl group is often referred to as a carbonyl compound. The term carbonyl can also refer to carbon monoxide as a ligand in an inorganic or organometallic complex (a metal carbonyl, e.g. nickel carbonyl). The remainder of this article concerns itself with the organic chemistry definition of carbonyl, such that carbon and oxygen share a double bond. Carbonyl compounds In organic chemistry, a carbonyl group characterizes the following types of compounds: Other organic carbonyls are urea and the carbamates, the derivatives of acyl chlorides, chloroformates and phosgene, carbonate esters, thioesters, lactones, lactams, Hydro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tetrahedral Carbonyl Addition Compound
A tetrahedral intermediate is a reaction intermediate in which the bond arrangement around an initially double-bonded carbon atom has been transformed from trigonal to tetrahedral. Tetrahedral intermediates result from nucleophilic addition to a carbonyl group. The stability of tetrahedral intermediate depends on the ability of the groups attached to the new tetrahedral carbon atom to leave with the negative charge. Tetrahedral intermediates are very significant in organic syntheses and biological systems as a key intermediate in esterification, transesterification, ester hydrolysis, formation and hydrolysis of amides and peptides, hydride reductions, and other chemical reactions. History One of the earliest accounts of the tetrahedral intermediate came from Rainer Ludwig Claisen in 1887. In the reaction of benzyl benzoate with sodium methoxide, and methyl benzoate with sodium benzyloxide, he observed a white precipitate which under acidic conditions yields benzyl benzoate, methy ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Organic Acid Anhydride
An organic acid anhydride is an acid anhydride that is also an organic compound. An acid anhydride is a compound that has two acyl groups bonded to the same oxygen atom. A common type of organic acid anhydride is a carboxylic anhydride, where the parent acid is a carboxylic acid, the formula of the anhydride being (RC(O))2O. Symmetrical acid anhydrides of this type are named by replacing the word ''acid'' in the name of the parent carboxylic acid by the word ''anhydride''. Thus, (CH3CO)2O is called ''acetic anhydride.'' ''Mixed'' (or ''unsymmetrical'') acid anhydrides, such as acetic formic anhydride (see below), are known, whereby reaction occurs between two different carboxylic acids. Nomenclature of unsymmetrical acid anhydrides list the names of both of the reacted carboxylic acids before the word "anhydride" (for example, the dehydration reaction between benzoic acid and propanoic acid would yield "benzoic propanoic anhydride"). One or both acyl groups of an acid anhydrid ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glutamic Acid
Glutamic acid (symbol Glu or E; known as glutamate in its anionic form) 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 GABAergic neurons. Its molecular formula is . Glutamic acid exists in two 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 s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tetrahedral Intermediate
A tetrahedral intermediate is a reaction intermediate in which the bond arrangement around an initially double-bonded carbon atom has been transformed from trigonal to tetrahedral. Tetrahedral intermediates result from nucleophilic addition to a carbonyl group. The stability of tetrahedral intermediate depends on the ability of the leaving group, groups attached to the new tetrahedral carbon atom to leave with the negative charge. Tetrahedral intermediates are very significant in organic syntheses and biological systems as a key intermediate in esterification, transesterification, ester hydrolysis, formation and hydrolysis of amides and peptides, hydride reductions, and other chemical reactions. History One of the earliest accounts of the tetrahedral intermediate came from Rainer Ludwig Claisen in 1887. In the reaction of benzyl benzoate with sodium methoxide, and methyl benzoate with sodium benzyloxide, he observed a white precipitate which under acidic conditions yields benzyl b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ligand
In coordination chemistry, a ligand is an ion or molecule with a functional group that binds to a central metal atom to form a coordination complex. The bonding with the metal generally involves formal donation of one or more of the ligand's electron pairs, often through Lewis acids and bases, Lewis bases. The nature of metal–ligand bonding can range from covalent bond, covalent to ionic bond, ionic. Furthermore, the metal–ligand bond order can range from one to three. Ligands are viewed as Lewis bases, although rare cases are known to involve Lewis acids and bases, Lewis acidic "ligands". Metals and metalloids are bound to ligands in almost all circumstances, although gaseous "naked" metal ions can be generated in a high vacuum. Ligands in a complex dictate the reactivity (chemistry), reactivity of the central atom, including ligand substitution rates, the reactivity of the ligands themselves, and redox. Ligand selection requires critical consideration in many practical are ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
