| beta-hydroxy-beta-methylglutaryl-CoA | -OOCCH2C(OH)(CH3)CH2COS-CoA;a key intermediate in the synthesis of ketone bodies and of steroids. Synonym: 3-hydroxy-3-methylglutaryl-CoA. Beta-hydroxy-beta-methylglutaryl-lyase, an enzyme, found primarily in liver and rumen epithelium that catalyses the formation of acetyl-CoA and acetoacetate from beta-hydroxy-beta-methylglutaryl-CoA; a key step in ketogenesis; a deficiency of this enzyme leads to episodes of severe metabolic acidosis without ketosis. Beta-hydroxy-beta-methylglutaryl-reductase, an enzyme that catalyses the rate-limiting step of cholesterol biosynthesis, beta-hydroxy-beta-methylglutaryl-CoA + 2NADPH + 2H+ → mevalonate + 2NADP+ + coenzyme A. Beta-hydroxy-beta-methylglutaryl-synthase, an enzyme in mitochondria that catalyses the reaction of acetyl-CoA with acetoacetyl-CoA and water to form beta-hydroxy-beta-methylglutaryl-CoA and coenzyme A, a step required for both ketogenesis and steroidogenesis to occur. (05 Mar 2000) |
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| beta-n-acetylglucosaminylglycopeptide beta-1,4-galactosyltransferase | <enzyme> An enzyme that catalyses the transfer of galactose from udp-galactose to a specific glycoprotein receptor, 2-acetamido-2-deoxy-d-glucosyl-glycopeptide, during glycopeptide synthesis. Chemical name: UDPgalactose:N-acetyl-beta-D-glucosaminylglycopeptide beta-1,4-galactosyltransferase Registry number: EC 2.4.1.38 (12 Dec 1998) |
| beta, or beta-value | <radiobiology> Ratio of plasma kinetic pressure to magnetic-field pressure, proportional to the ratio of plasma kinetic energy density to magnetic field energy density. Beta is usually measured relative to the total, local field (loosely called beta toroidal), but sometimes the plasma pressure relative to only the poloidal component of the field (beta poloidal) or relative to some external field (like the maximum field at the magnetic coils) is more useful. There is also a normalised beta (beta_N) of interest when discussing the beta limit. (lots of help from Art Carlson with the above.) Because the cost of a reactor is strongly influenced by the strength of the magnetic field that must be provided, beta values are directly related to the economics of fusion power production. Beta is usually expressed as a percentage, with 5% generally believed to be the minimum value required for an economical fusion reactor. See: pressure, kinetic pressure, magnetic pressure, second stability. (09 Oct 1997) |
| UDP-GalNAc-beta-galactose beta 1,4-N-acetylgalactosaminyltransferase | <enzyme> Consider also EC 2.4.1.92 Registry number: EC 2.4.1.- Synonym: beta-1,4-n-acetylgalactosaminyltransferase, 4-galnactransferase, udp-n-acetylgalactosamine-beta-galactose beta 1,4-n-acetylgalactosaminyltransferase, (1-4)-n-acetyl-beta-d-galactosaminyltransferase, galnact-1 (26 Jun 1999) |
| 5 alpha-androstane-3 beta,17 beta-diol 6 alpha-hydroxylase | <enzyme> Requires NADPH, found in rat prostatic microsomes Registry number: EC 1.14.13.- Synonym: artdl 6 alpha-hydroxylase (26 Jun 1999) |
| 5 alpha-androstane 3 beta,17 beta-diol 7 alpha-hydroxylase | <enzyme> Requires NADPH, found in rat prostate microsomes Registry number: EC 1.14.13.- Synonym: artdl 7 alpha-hydroxylase (26 Jun 1999) |
| acetyl CoA-(beta-aminoethyl)-L-cysteine omega-N-acetyltransferase | <enzyme> Forms s-(beta-n-acetyl-aminoethyl)-l-cysteine Registry number: EC 2.3.1.- Synonym: acoac-acetyltransferase, acetyl coenzyme a-(beta-aminoethyl)-l-cysteine omega-n-acetyltransferase (26 Jun 1999) |
| acetylgalactosaminylgalactosylgalactosylglucosylceramide beta-D-acetylgalactosaminyltransferase | <enzyme> Forms galnac-beta1-3galnac-beta1-3gal-alpha1-4gal-beta1-4glc-cer Registry number: EC 2.4.1.- Synonym: forssman glycolipid synthase, udp-galnac globotetraoside n-acetylgalactosaminyl transferase (26 Jun 1999) |
| acetylgalactosaminyl-O-glycosyl-glycoprotein beta-1,3-N-acetylglucosaminyltransferase | <enzyme> Forms oligosaccharide core class 3 (glcnac beta 1-3galnac) in mucins and various glycoproteins Registry number: EC 2.4.1.147 Synonym: udp-glcnac-galnac-r beta 3-acetylglucosaminyltransferase, agggag-transferase (26 Jun 1999) |
| acyl-CoA-estradiol-17-beta-acyltransferase | <enzyme> Catalyses the esterification of estradiol with long chain fatty acids at the 17-position Registry number: EC 2.3.1.- Synonym: acylcoenzyme a-estradiol-17-beta-acyltransferase, estradiol 17-acyltransferase (26 Jun 1999) |
| adrenergic beta-agonists | Drugs that selectively bind to and activate beta-adrenergic receptors. (12 Dec 1998) |
| adrenergic beta-antagonists | Drugs that bind to but do not activate beta-adrenergic receptors thereby blocking the actions of beta-adrenergic agonists. Adrenergic beta-antagonists are used for treatment of hypertension, cardiac arrythmias, angina pectoris, glaucoma, migraine headaches, and anxiety. (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-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,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) |