| alpha-allopregnanediol | 5alpha-Pregnane-3a,20alpha-diol;a metabolite of progesterone and adrenocortical hormones, found in urine. (05 Mar 2000) |
|---|---|
| alpha-amanitin | <drug> A highly toxic, heat-stable bicyclic oligopeptide derived from the Amanita phalloides mushroom. It inhibits transcription by interfering with the function of certain RNA polymerases. (14 Aug 2000) |
| alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid | <chemical> Alpha-amino-2,3-dihydro-5-methyl-3-oxo-4-isoxazolepropanoic acid. An ibotenic acid homolog and glutamate agonist. The compound is the defining agonist for the ampa subtype of glutamate receptors (receptors, ampa). It has been used as a radionuclide imaging agent but is more commonly used as an experimental tool in cell biological studies. Pharmacological action: excitatory amino acid agonists. Chemical name: 4-Isoxazolepropanoic acid, alpha-amino-2,3-dihydro-5-methyl-3-oxo- (12 Dec 1998) |
| alpha-amino acid | Typically, an amino acid of the general formula R-CHNH2-COOH (i.e., the NH2 in the a position); the l forms of these are the hydrolysis products of proteins. In rarer usages, this class of molecules also includes alpha-amino phosphoric acids and alpha-aminosulfonic acids. (05 Mar 2000) |
| alpha-amino acid esterase | <enzyme> Converts alpha-amino acid esters and water to alpha-amino acids and alcohol Registry number: EC 3.1.1.43 Synonym: alpha-amino acid ester hydrolase (26 Jun 1999) |
| alpha-aminoacyl-peptide hydrolases | <enzyme> Registry number: EC 3.4.11. (12 Dec 1998) |
| alpha-aminoadipic acid | 2-amino-1,6-hexanedioic acid;an intermediate of lysine biosynthesis in higher fungi and bacteria, but not in algae and higher plants. Also in degradation of lysine in mammals. (05 Mar 2000) |
| alpha-aminoadipyl-cysteinyl-valine synthetase | <enzyme> As of 9/27/95 this has been separated from isopenicillin n synthetase Registry number: EC 6.3.2.- Synonym: acv synthetase, aa-cysteine synthetase, delta-(alpha-aminoadipyl)-cys-val synthetase, delta-(l-alpha-aminoadipyl)-l-cyteinyl-d-valine synthetase, pcbab gene product, acva gene product (26 Jun 1999) |
| alpha-amino-beta-ketoadipic acid | 2-Amino-3-oxo-1,6-hexanedioic acid;an intermediate of porphobilinogen synthesis formed by d-aminolevulinic acid synthase from succinyl-CoA and glycine; it rapidly decarboxylates to d-aminolevulinic acid. (05 Mar 2000) |
| alpha-aminoglutaric acid | <amino acid> One of the 20 _ amino acids commonly found in proteins. Plays a central role in amino acid metabolism, acting as precursor of glutamine, proline and arginine. Also acts as amino group donor in synthesis by transamination of alanine from pyruvate and aspartic acid from oxaloacetate. Glutamate is also a neurotransmitter, the product of its decarboxylation is the inhibitory neurotransmitter amino butyrate (GABA). (18 Nov 1997) |
| alpha-aminoisobutyric acid | 2-amino-2-methylpropionic acid;a synthetic amino acid useful in the study of amino acid transport across cell membranes and in the study of cytokine effects; it is not metabolised by the cell. (05 Mar 2000) |
| alpha-aminosuccinic acid | <amino acid> One of the twenty naturally occurring amino acids. Has the following chemical characteristics: pKa1 pKa2 pKa3 pI Water Solubility (30deg C)2.09-3.86 9.82 2.97 0.6 (09 Oct 1997) |
| alpha-amylase | <enzyme> An enzyme that catalyses the endohydrolysis of 1,4-alpha-glycosidic linkages in starch, glycogen, and related polysaccharides and oligosaccharides containing 3 or more 1,4-alpha-linked d-glucose units. Pharmacological action: anti-inflammatory agents. Chemical name: 1,4-alpha-D-Glucan glucanohydrolase Registry number: EC 3.2.1.1 (12 Dec 1998) |
| alpha angle | The angle between the visual and optic axes as they cross at the nodal point of the eye, the angle between the visual line and the major axis of the corneal ellipse. (05 Mar 2000) |
| alpha-antitrypsin deficiency | <enzyme> A specific enzyme (alpha 1 antitrypsinase) that when absent genetically can result in panacinar emphysema (lung disease) and liver disease. There is no specific treatment for this condition other than supportive care for the liver and lung complications. Medications such as alpha-1proteinase inhibitor is given regularly to these patients. Incidence: approximately 1 in 10,000. (02 Jan 1998) |