| beta-aminoisobutyric acid | 3-Amino-2-methylpropionic acid;an end product of thymine catabolism; high urinary levels (200-300 mg/day) have been noted in some individuals, either from some disease process or following a genetic pattern. (05 Mar 2000) |
|---|---|
| beta-aminoisobutyric acid oxidase | <enzyme> Fad-stimulated, probably forms methylmalonylsaemialdehyde Registry number: EC 1.4.3.- Synonym: baib-oxidase (26 Jun 1999) |
| beta-hydroxybutyric acid | CH3CH(OH)CH2COOH;the d-stereoisomer is one of the ketone bodies and is formed in ketogenesis; it is an important fuel for extrahepatic tissues; as an acyl derivative it is also an intermediate in fatty acid biosynthesis. The l-isomer is found as a coenzyme A derivative in b oxidation of fatty acids. Synonym: 3-hydroxybutanoic acid, beta-hydroxybutyric acid. D-3-hydroxybutyric acid dehydrogenase, an enzyme that reversibly catalyses the interconversion of the two main ketone bodies, catalyzing acetoacetate + NADH + H+ &dblarr; d-3-hydroxybutyrate + NAD+. (05 Mar 2000) |
| beta-hydroxyisobutyric acid | HOCH2CH(CH3)COOH;an intermediate in the degradation of l-valine. (05 Mar 2000) |
| beta-hydroxypropionic acid | A minor intermediate in propionate and methylmalonate metabolism. See: beta-hydroxypropionic aciduria. (05 Mar 2000) |
| beta-sulfinylpyruvic acid | <biochemistry> An intermediate product of l-cysteine catabolism in mammalian tissue. Structure: HO2S-CH2-CO-COOH (05 Mar 2000) |
| betulinic acid | This pentacyclic terpene isfound in the bark of birch trees, especially the white birch (Betula alba). It is currently beinginvestigated as a treatment for malignant melanoma. (09 Oct 1997) |
| bile acid 7alpha-dehydratase | <enzyme> Enzyme in the bacterial bile acid 7alpha-dehydroxylation pathway Registry number: EC 4.2.1.- Synonym: c24 bile acid 7alpha-dehydratase, ba7alphad, baie gene product (26 Jun 1999) |
| bile acid 7 alpha-dehydroxylase | <enzyme> Mechanism is questionable: cholic acid - deoxycholic acid - chenodeoxycholic acid - lithocholic acid Registry number: EC 1.14.- Synonym: 7 alpha-dehydroxylase, bile acid 7-dehydroxylase, bile acid 7-alpha-dehydroxylase, bai a1, bai a2, bai a3, cholic acid 7alpha-dehydroxylase (26 Jun 1999) |
| bile acid-CoA ligase | <enzyme> Catalyses the synthesis of all bile acid-coas; in order to measure the activity of all bile acids, the bile acid is coupled with c(14)-glycine and measured with bile acid-CoA glycine-taurine n-acetyltransferase Registry number: EC 6.2.1.- (26 Jun 1999) |
| bile acid tolerance test | A sensitive test of hepatic dysfunction; following oral administration of labelled or unlabelled bile acid, the measured fractional disappearance rate or 10-minute retention is measured. (05 Mar 2000) |
| binary acid | <chemistry> This refers to any compound that acts as an acid and which is composed of hydrogen plus only one other element. (09 Oct 1997) |
| boletic acid | An obsolete term for fumaric acid. (05 Mar 2000) |
| bongkrekic acid | <chemical> An antibiotic produced by pseudomonas cocovenenans. It inhibits adenine nucleotide efflux from mitochondria by enhancing membrane binding. Pharmacological action: antibiotics. Chemical name: 2,4,8,10,14,18,20-Docosaheptaenedioic acid, 20-(carboxymethyl)-6-methoxy-2,5,17-trimethyl-, (R-(R*,S*-(E,Z,Z,E,E,Z,E)))- (12 Dec 1998) |
| boracic acid | H3BO3;a very weak acid, used as an antiseptic dusting powder, in saturated solution as a collyrium, and with glycerin in aphthae and stomatitis. Synonym: boracic acid. (05 Mar 2000) |