| peptide chain termination | The process whereby the last amino acid is added to a polypeptide. This termination is signaled by one of three termination triplets in the mRNA, immediately following the last amino acid codon. (12 Dec 1998) |
|---|---|
| chain, orthodontic chain | <dentistry> A stretchable plastic chain used to hold archwires into brackets and to moke teeth. (08 Jan 1998) |
| peptide termination factors | Proteins that are exclusively involved in the termination reactions of protein synthesis on the ribosome. (12 Dec 1998) |
| termination | <molecular biology> Stop of mRNA synthesis (i.e., transcription) at the terminator site Top of protein synthesis (i.e., translation) at the stop codon. (09 Oct 1997) |
| termination codon | <molecular biology> The three codons, UAA known as ochre, UAG as amber and UGA as opal, that do not code for an amino acid but act as signals for the termination of protein synthesis. They are not represented by any tRNA and termination is catalysed by protein release factors. There are two release factors in E. Coli, RF1 recognises UAA and UAG, RF2 recognises UAA and UGA. Eukaryotes have a single GTP requiring factor, eRF. See: ochre suppressor, amber suppressor. (13 Jan 1998) |
| termination factor | <molecular biology> Any of several proteins in the cytosol that cut a completed polypeptide loose from a ribosome. (13 Jan 1998) |
| termination region | <molecular biology> A DNA sequence that signals the end of transcription. (13 Jan 1998) |
| termination sequence | <molecular biology> The three codons, UAA known as ochre, UAG as amber and UGA as opal, that do not code for an amino acid but act as signals for the termination of protein synthesis. They are not represented by any tRNA and termination is catalysed by protein release factors. There are two release factors in E. Coli, RF1 recognises UAA and UAG, RF2 recognises UAA and UGA. Eukaryotes have a single GTP requiring factor, eRF. See: ochre suppressor, amber suppressor. (13 Jan 1998) |
| A chain | A polypeptide component of insulin containing 21 amino acyl residues, beginning with a glycyl residue (NH2-terminus); insulin is formed by the linkage of an A chain to a B chain by two disulfide bonds; the amino-acid composition of the A chain is a function of species. Synonym: glycyl chain. In general, one of the polypeptides in a multiprotein complex. (05 Mar 2000) |
| alpha chain disease | A vague or indefinite term; could be used for alpha-heavy-chain disease (a lymphoplasma cell proliferative disease usually seen in Mediterranean men, characterised by intestinal involvement with steatorrhoea, often progressive with fatal outcome) or a thalassaemia (a genetic abnormality in the alpha globin chain of haemoglobin). (05 Mar 2000) |
| amino acids, branched-chain | Amino acids which have a branched carbon chain. (12 Dec 1998) |
| B chain | A polypeptide component of insulin containing 30 amino acyl residues, beginning with a phenylalanyl residue (NH2-terminus); insulin is formed by the linkage of a B chain to an A chain by two disulfide bonds; the amino-acid composition of the B chain is a function of species. Synonym: phenylalanyl chain. (05 Mar 2000) |
| behaviour chain | Related behaviours in a series in which each response serves as a stimulus for the next response. (05 Mar 2000) |
| branched chain acyl-CoA oxidase | <enzyme> Enzyme from human liver peroxisomes acts on both 2-methyl branched fatty acyl- and bile acid-CoA intermediates, unlike rat liver peroxisomes which have separate enzymes for branched chain fatty acids (pristanoyl-CoA) and bile acid-CoA; involved in beta-oxidation of fatty acids and bil Registry number: EC 1.3.3.- Synonym: 2-methyl-branched chain acyl-CoA oxidase, hbrcacox (26 Jun 1999) |
| branched-chain fatty-acid-kinase | <enzyme> From anaerobic spirochete ma-2 Registry number: EC 2.7.2.14 Synonym: isovalerate kinase, 2-methylbutyrate kinase, isobutyrate kinase (26 Jun 1999) |