| hydroxymethyluracil DNA glycosylase | <enzyme> Functions to eliminate hydroxymethyluracil from oxidatively damaged DNA Registry number: EC 3.2.2.- Synonym: hmu DNA glycosylase (26 Jun 1999) |
|---|---|
| hydroxynervone | A cerebroside containing alpha-hydroxynervonic acid. Synonym: oxynervone. (05 Mar 2000) |
| hydroxynervonic acid | CH3-(CH2)7-CH==CH-(CH2)12-CH(OH)COOH;an important constituent of certain cerebrosides. (05 Mar 2000) |
| hydroxyneurosporene desaturase | <enzyme> Involved in carotenoid biosynthesis; specific for hydroxyneurosporene; requires molecular oxygen for the c-3,4 desaturation reaction; isolated from rhodobacter sphaeroides; do not confuse with crtd gene product for methoxyneurosporene desaturase Registry number: EC 1.3.3.- Synonym: crtd gene product (hydroxyneurosporene), crtd ohn (26 Jun 1999) |
| hydroxyphenamate | 2-Hydroxy-2-phenylbutyl carbamate;a tranquilliser. (05 Mar 2000) |
| hydroxyphenylazouracil | <chemical> Inhibitor of DNA replication in gram-positive bacteria. Pharmacological action: nucleic acid synthesis inhibitors. (12 Dec 1998) |
| hydroxyphenyluria | Urinary excretion of tyrosine and phenylalanine, as a result of ascorbic acid deficiency; occurs notably in those premature infants who lack this vitamin. (05 Mar 2000) |
| hydroxypregnenolone | <chemical> Chemical name: Pregn-5-en-20-one, 3,?-dihydroxy-, (3beta)- (12 Dec 1998) |
| hydroxyprolinaemia | A metabolic disorder characterised by enhanced plasma concentrations and urinary excretion of free hydroxyproline, and associated with severe mental retardation; autosomal recessive inheritance. (05 Mar 2000) |
| hydroxyproline | Specific proline residues on the amino side of a glycine residue in collagen become hydroxylated at C4, before the polypeptides become helical, by the activity of prolyl hydroxylase. This enzyme has a ferrous ion at the active site and a reducing agent such as ascorbate is necessary to maintain the iron in the ferrous state. The presence of hydroxyproline is essential to produce stable triple helical tropocollagen, hence the problems caused by ascorbate deficiency in scurvy. This unusual amino acid is also present in considerable amounts in the major glycoprotein of primary plant cell walls (see HRGP). (18 Nov 1997) |
| hydroxyproline oxidase | <enzyme> Oxidises 4-hydroxy-l-proline to delta'-pyrroline-3-hydroxy-5-carboxylate Registry number: EC 1.5.99.- (26 Jun 1999) |
| hydroxyproline rich glycoprotein | See: HRGP. (18 Nov 1997) |
| hydroxypropiophenone | <chemical> Chemical name: 1-Propanone, 1-phenyl-, monohydroxy deriv. (12 Dec 1998) |
| hydroxyprostaglandin dehydrogenases | <enzyme> Catalyses reversibly the oxidation of hydroxyl groups of prostaglandins. Registry number: EC 1.1.1.- (12 Dec 1998) |
| hydroxypyruvate decarboxylase | <enzyme> Catalyses the nonoxidative decarboxylation of hydroxypyruvate to glycolaldehyde and co2; present in a variety of tissues in a number of species Registry number: EC 4.1.1.40 Synonym: hydroxypyruvate carboxy-lyase (26 Jun 1999) |