| alpha viruses | <virology> These are the major viruses in the Togavirus group and include eastern and western equine encephalitis viruses, the Sindbis virus and the Semliki Forest virus. The last two viruses are being researched as vectors for expressing heterologous genes. (09 Oct 1997) |
|---|---|
| alpha wave | Brain waves in the encephalogram which have a frequency of 8 to 13 per second. They are typical of the normal person awake and in a quiet resting state, and occur principally in the occipital region. (12 Dec 1998) |
| alpha(1-6)mannosidase | <enzyme> Human lysosomal enzyme highly specific for alpha 1-6 mannose residues; inhibited by swainsonine; not the same enzyme which is deficient in alpha-mannosidosis Registry number: EC 3.2.1.- (26 Jun 1999) |
| alpha(2,8)-sialyltransferase | <enzyme> Active towards gm1b, gd1a, gt1b, and gd3 gangliosides; genbank u91641 Registry number: EC 3.4.99.- Synonym: st8sia v, hst8sia v (26 Jun 1999) |
| alpha, alpha-phosphotrehalase | <enzyme> Forms glucose plus glucose-6-phosphate Registry number: EC 3.2.1.93 Synonym: trehalose-6-phosphate hydrolase, phospho-alpha(1,1)glucosidase, trea gene product, trec gene product (26 Jun 1999) |
| alpha,alpha-trehalose phosphorylase | <enzyme> Chemical name: alpha-d-glucopyranosyl-alpha-d-glucopyranose orthophosphate glucosyltransferase Registry number: EC 2.4.1.64 Synonym: trehalose phosphorylase (26 Jun 1999) |
| alpha,beta-ketoalkene reductase | <enzyme> Nadh is much less effective than NADPH; catalyses the reduction of the carbon-carbon double bond of five membered ring cpds which have two conjugated carbonyl groups on both sides of a double bond Registry number: EC 1.3.1.- Synonym: n-ethylmaleimide reducing enzyme, NADPH-linked alpha,beta-ketoalkene double bond reductase, n-ethylmaleimide reductase (26 Jun 1999) |
| alpha-(4-O-methyl)-D-glucuronidase | <enzyme> Removes 4-o-methyl-glucopyranosyl uronic acid residues from the 2-position of fungal cell wall xylans Registry number: EC 3.2.1.- Synonym: 4-o-methyl-glucuronidase (26 Jun 1999) |
| alpha-(N-acetylaminomethylene)succinic acid hydrolase | <enzyme> Involved in degradation of vitamin b6; forms acetic acid plus ammonia plus carbon dioxide plus succinic monoaldehyde Registry number: EC 3.5.1.- Synonym: compound a hydrolase (26 Jun 1999) |
| alpha-1 antichymotrypsin | <chemical> Glycoprotein found in alpha(1)-globulin region in human serum. It is an inhibiter of the digestive protease, chymotrypsin and other chymotrypsin-like proteinases in vivo and has cytotoxic killer-cell activity in vitro. The protein also has a role as an acute-phase protein and is active in the control of immunologic and inflammatory processes, and as a tumour marker. It is a member of the serpin superfamily. Pharmacological action: serine proteinase inhibitors. (12 Dec 1998) |
| alpha-1 antitrypsin | <chemical> Plasma glycoprotein member of the serpin superfamily which inhibits trypsin, neutrophil elastase, and other proteolytic enzymes. Commonly referred to as alpha 1-proteinase inhibitor (a1pi), it exists in over 30 different biochemical variant forms known collectively as the pi (protease inhibitor) system. Hereditary deficiency is associated with pulmonary emphysema. See: alpha-1 antitrypsin deficiency Pharmacological action: serine proteinase inhibitors, trypsin inhibitors. (12 Dec 1998) |
| alpha-1 antitrypsin deficiency | <chest medicine> Deficiency of the protease inhibitor alpha-1 antitrypsin, leads primarily to degradation of elastin of the alveolar walls, as well as other structural proteins of a variety of tissues. The lack of this protein leads to damage of various organs, but mainly to the lung and liver. symptoms may become apparent at a very early age or in adulthood, manifesting either as shortness of breath or liver related symptoms (jaundice, fatigue, fluid in the abdomen, mental changes, or gastrointestinal bleeding). There are several options for treatment of the lung disease, including replacement of the missing protein. Treatment of the liver disease is a well-timed liver transplant (12 Dec 1998) |
| alpha-1,3-mannosylglycoprotein beta-1,4-N-acetylglucosaminyltransferase | <enzyme> Incorporates n-acetyglucosamine as the third branch of complex n-glycosyl-oligosaccharide of hen oviduct Registry number: EC 2.4.1.145 Synonym: glcnac-transferase iv, n-acetylglucosaminyltransferase iv, udp-glcnac-gngn(glcnac to man alpha1-3)beta 4-n-acetylglucosaminyltransferase iv (26 Jun 1999) |
| alpha-1,4-glucan lyase | <enzyme> Degrades alpha-1,4-glucan to produce 1,5-anhydrofructose; from seaweeds gracilariopsis lemaneiformis and gracilaria verrucosa; mw 111 kD; amino acid sequence has been determined Registry number: EC 4.2.2.- Synonym: alpha-1,4-glucan 4-lyase (26 Jun 1999) |
| alpha-1-proteinase deficiency | Absence of a serum proteinase inhibitor that may cause nodular non-suppurative panniculitis. (05 Mar 2000) |
| genes, T-cell receptor alpha | DNA sequences encoding the alpha chain of the T-cell receptor. The genomic organization of the tcr alpha genes is essentially the same in all species and is similar to the organization of ig genes. (12 Dec 1998) |
|---|---|
| receptors, adrenergic, alpha | One of the two major pharmacological subdivisions of adrenergic receptors. The alpha-beta distinction was originally based on cellular effects of receptor activation but now relies on the relative affinities for certain synthetic ligands. Alpha-adrenergic receptors are further subdivided into several subclasses based on studies of endogenous and cloned receptors. (12 Dec 1998) |
| receptors, adrenergic, alpha-1 | A subclass of alpha-adrenergic receptors (receptors, adrenergic, alpha). Alpha-1 adrenergic receptors can be pharmacologically discriminated, e.g., by their high affinity for the agonist phenylephrine and the antagonist prazosin. They are widespread, with clinically important concentrations in the liver, the heart, vascular, intestinal, and genitourinary smooth muscle, and the central and peripheral nervous systems. (12 Dec 1998) |
| receptors, adrenergic, alpha-2 | A subclass of alpha-adrenergic receptors (receptors, adrenergic, alpha). Alpha-2 adrenergic receptors can be pharmacologically discriminated, e.g., by their high affinity for the agonist clonidine and the antagonist yohimbine. They are found on pancreatic beta cells, platelets, and vascular smooth muscle, as well as both pre- and postsynaptically in the central and peripheral nervous systems. (12 Dec 1998) |
| receptors, antigen, T-cell, alpha-beta | T-cell receptors composed of CD3-associated alpha and beta polypeptide chains and expressed primarily in CD4+ or CD8+ T-cells. Unlike immunoglobulins, the alpha-beta T-cell receptors recognise antigens only when presented in association with major histocompatibility (MHC) molecules. (12 Dec 1998) |
| maternal serum alpha-fetoprotein | A plasma protein, alpha-fetoprotein (afp) is normally produced by the foetus. The level of afp in the blood serum of pregnant women provides a screening test for open neural tube defects (anencephaly and spina bifida) and for down syndrome (and other chromosome abnormalities). The maternal serum afp (msafp) tends to be unusally high with open neural tube defects and unsually low with down syndrome. (12 Dec 1998) |
| glucan 1,4-alpha-glucosidase | <enzyme> An enzyme that catalyses the hydrolysis of terminal 1,4-linked alpha-d-glucose residues successively from non-reducing ends of polysaccharide chains with the release of beta-glucose. It is also able to hydrolyze 1,6-alpha-glucosidic bonds when the next bond in sequence is 1,4. Chemical name: 1,4-alpha-D-Glucan glucohydrolase Registry number: EC 3.2.1.3 (12 Dec 1998) |
| glucan 1,4-alpha-maltohexaosidase | <enzyme> From klebsiella pneumoniae; hydrolyzes 1,4-alpha-d-glucosidic linkages in amylaceous polysaccharides so as to remove successive maltohexaose residues from the non-reducing ends Registry number: EC 3.2.1.98 Synonym: exo-maltohexao-hydrolase, extracellular maltohexaose-forming amylase, bacillus maltohexaose-forming amylase, g6-amylase (26 Jun 1999) |
| glucan 1,6-alpha-isomaltosidase | <enzyme> Hydrolyzes 1,6-alpha-d-glucosidic linkages in polysaccharides so as to remove successive isomaltose units from the non-reducing ends of the chains; from arthrobacter globiformis; mw 66 kD; genbank d30761 Registry number: EC 3.2.1.94 Synonym: isomalto-dextranase, 1,6-alpha-d-glucan isomaltohydrolase, imd gene product, exo-isomaltohydrolase (26 Jun 1999) |
| cephalosporin 7-alpha-hydroxylase | <enzyme> A dioxygenase from streptomyces clavuligerus; requires 2-oxoglutarate, fe2+ and a reducing agent such as ascorbic acid Registry number: EC 1.14.11.- (26 Jun 1999) |
| glycopeptide alpha-N-acetylgalactosaminidase | <enzyme> Hydrolyzes terminal d-galactosyl-n-acetyl-alpha-d-galactosaminide residues from glycopeptides and glycoproteins linked by serine or threonine residues Registry number: EC 3.2.1.97 Synonym: o-glycanase (26 Jun 1999) |
| glycoprotein endo-alpha-1,3-mannosidase | <enzyme> An endomannosidase; cleaves glucosyl alpha1-3-mannose from monoglucosylated oligosaccharide (glcman(7-9)glcnac) of the glycoprotein produced in the golgi membrane Registry number: EC 3.2.1.130 Synonym: glucosyl mannosidase (26 Jun 1999) |
| glycoprotein hormones, alpha subunit | A non-covalently bound subunit of the glycoprotein hormones tsh, fsh, lh, and hcg which originates in the anterior pituitary gland and placenta. This subunit is virtually identical in structure and indistinguishable by radioimmunoassay in all of the above glycoproteins. It is present in both men and women, but is elevated in postmenopausal women and in patients with hypothyroidism, uraemia and malignant tumours. The alpha subunit may be involved directly in recognition of certain receptors. (12 Dec 1998) |
| glycosylated alpha-amylase | <enzyme> Contains a single biantennary n-linked oligosaccharide that terminates with the structure fucalpha1,3(galbeta1,4)glcnac Registry number: EC 3.2.1.- Synonym: human glycosylated alpha-amylase (26 Jun 1999) |
| peptide N-alpha acetyltransferase | <enzyme> Pituitary enzyme; acetylates peptide hormones including acth; also found in saccharomyces cerevisiae Registry number: EC 2.3.1.88 Synonym: peptide acetyltransferase, acth acetyltransferase, beta-endorphin acetyltransferase, alpha-msh acetyltransferase (26 Jun 1999) |