| nonpolar amino acid | An alpha-amino acid in which the functional group attached to the alpha-carbon (i.e., R in RCH(NH2)COOH) has hydrophobic properties; e.g., valine, leucine, alpha-aminobutyrate. (05 Mar 2000) |
|---|---|
| D-amino acid malonyltransferase | <enzyme> From mung beans Registry number: EC 2.3.1.- Synonym: 1-aminocyclopropanecarboxylate malonyltransferase, d-acc-malonyltransferase, acc n-malonyltransferase (26 Jun 1999) |
| d-amino-acid oxidase | <enzyme> Chemical name: D-Amino-acid:oxygen oxidoreductase (deaminating) Registry number: EC 1.4.3.3 (12 Dec 1998) |
| D-amino acid transaminase | <enzyme> Catalyses the alpha,beta elimination of the (d)-isomer of beta-chloroalanine or other amino acids to yield pyruvate, chloride and ammonia Registry number: EC 2.6.1.- (26 Jun 1999) |
| D-amino acid transferase | <enzyme> Mw 41 kD; catalyses d-amino acid transfer; d-configuration specific; recognises aromatic d-amino acid esters to form oligo d-amino acid esters Registry number: EC 2.3.2.- (26 Jun 1999) |
| dibasic amino acid | An amino acid containing a second basic group (usually an amino group); e.g., lysine, arginine, ornithine. Synonym: dibasic amino acid. (05 Mar 2000) |
| essential amino acid | <biochemistry> Those amino acids that cannot be synthesised by an organism and must therefore be present in the diet. The term is often applied anthropocentrically to those amino acids required by humans (Ileu, Leu, Lys, Met, Phe, Thr, Try, & Val), though rats need two more (Arg & His). (18 Nov 1997) |
| excitatory amino acid | <biochemistry> The naturally occurring amino acids L glutamate and L aspartate and their synthetic analogues, notably kainate, quisqualate and NMDA. They have the properties of excitatory neurotransmitters in the CNS, may be involved in long-term potentiation and can act as excitotoxins. at least three classes of EAA receptor have been identified, the agonists of the N type receptor are L aspartate, NMDA and ibotenate, the agonists of the Q type receptor are L glutamate and quisqualate, agonists of the K type are L glutamate and kainate. All three receptor types are found widely in the CNS and particularly the telencephalon, N and Q type receptors tend to occur together and may interact, their distribution is complementary to the K type receptors. The ion fluxes through the Q and K receptors are relatively brief, whereas the flux through the N type is longer and carries a significant amount of calcium. Additionally the N type receptor is blockaded by magnesium near the resting potential and thus shows voltage gated ion channel properties, leading to a regenerative response, this is why N type receptors have been linked to long-term potentiation. Invertebrate glutamate receptors may not have the same properties as those described above. (18 Nov 1997) |
| excitatory amino acid agents | Drugs used for their actions on any aspect of excitatory amino acid neurotransmitter systems. Included are drugs that act on excitatory amino acid receptors, affect the life cycle of excitatory amino acid transmitters, or affect the survival of neurons using excitatory amino acids. (12 Dec 1998) |
| excitatory amino acid agonists | Drugs that bind to and activate excitatory amino acid receptors. (12 Dec 1998) |
| excitatory amino acid antagonists | Drugs that bind to but do not activate excitatory amino acid receptors, thereby blocking the actions of agonists. (12 Dec 1998) |
| 1-carbamoyl-L-amino acid amidohydrolase | <enzyme> From bacillus stearothermophilus; amino acid sequence given in first source Registry number: EC 3.5.1.- Synonym: carbamoyl l-aa amidohydrolase, n-carbamyl-l-amino acid amidohydrolase (26 Jun 1999) |
| amino- | <prefix> Prefix denoting a compound containing the radical, -NH2. Origin: an(monia) + in(e) + -o- (05 Mar 2000) |
| amino acids | Organic compounds that generally contain an amino (-nh2) and a carboxyl (-cooh) group. Twenty alpha-amino acids are the subunits which are polymerised to form proteins. (12 Dec 1998) |
| amino acids, branched-chain | Amino acids which have a branched carbon chain. (12 Dec 1998) |