| ketogenic | Giving rise to ketone bodies in metabolism. (05 Mar 2000) |
|---|---|
| ketogenic-antiketogenic ratio | The proportion between substances that form ketones in the body and those that form d-glucose. (05 Mar 2000) |
| ketogenic corticoids test | A colourimetric test, based on the Zimmermann reaction, which indicates metabolites or adrenal and testicular steroids excreted as 17-ketones in the urine; increased values are most striking in adrenocortical tumours, decreased values in Addison's disease or in panhypopituitarism. Synonym: ketogenic corticoids test. (05 Mar 2000) |
| ketogenic diet | A high-fat, low-carbohydrate, and normal protein diet causing ketosis. (05 Mar 2000) |
| 17-ketogenic steroid assay test | A colourimetric test, based on the Zimmermann reaction, which indicates metabolites or adrenal and testicular steroids excreted as 17-ketones in the urine; increased values are most striking in adrenocortical tumours, decreased values in Addison's disease or in panhypopituitarism. Synonym: ketogenic corticoids test. (05 Mar 2000) |
| acidic amino acid | An Amino acid with a second acid moiety, e.g., glutamic acid, aspartic acid, cysteic acid. (05 Mar 2000) |
| activated amino acid | The product formed by the condensation of the acyl radical of an amino acid and adenosine 5'-monophosphate (originally in the form of adenosine 5'-triphosphate, with elimination of a pyrophosphoric group). Formed in the first step of protein biosynthesis. Synonym: activated amino acid. (05 Mar 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-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) |
| amino acid | <biochemistry> A class of organic molecules that containing an amino group and can combine in linear arrays to form proteins in living organisms. There are twenty common amino acids: alanine, arginine, aspargine, aspartic acid, cysteine, glutamic acid, glutamine, glycine, histidine, isoleucine, leucine, lysine, methionine, phenylalanine, proline, serine, threonine, tryptophan, tyrosine, and valine. They are key components in all living things from which proteins are synthesised by formation of peptide bonds during ribosomal translation of messenger RNA. All the amino acids have the L configuration, except glycine which is not optically active. Other amino acids occurring in proteins, such as hydroxyproline in collagen, are formed by post translational enzymatic modification of amino acid residues in polypeptide chains. There are also several important amino acids, such as the neurotransmitter y aminobutyric acid, that have no relation to proteins. Amino acids can now be produced by biotechnology in bulk using fermentation and biotransformation. Acronym: AA (13 Nov 1997) |
| amino acid activating enzyme | <enzyme> Enzymes catalyzing the formation of a specific aminoacyl-tRNA from an amino acid and adenosine 5'-triphosphate with the concomitant formation of adenosine 5'-monophosphate and pyrophosphate. Synonym: amino acid activating enzyme, aminoacyl-tRNA ligases. (05 Mar 2000) |
| amino acid activation | The first step of protein synthesis, whereby an amino acid reacts with adenosine triphosphate in the presence of aminoacyl RNA synthetase to produce an amino acid adenylate, which provides the energy necessary for the attachment of the amino acid to a specific transfer RNA molecule. (12 Dec 1998) |
| amino acid analysis | Determination and identification of amino acid content of a macromolecule, identification of a specific amino acid in macromolecules, often a mutated protein, identification and quantitation of amino acid content in blood plasma or urine; a key diagnostic aid. (05 Mar 2000) |