monophenol monooxygenase


monophenol monooxygenase
1. A copper-containing oxidoreductase that catalyzes the oxidation of o-diphenols to o-quinones by O2, with the incorporation of one of the two oxygen atoms in the product; it also catalyzes the oxidation of monophenols, such as l-tyrosine, to dihydroxy-l-phenylalanine (dopa), a precursor of melanin and epinephrine (catecholamines), and can act as a catechol oxidase; a deficiency of this enzyme is observed in a number of forms of albinism. SYN: cresolase, monophenol oxidase, tyrosinase. 2. SYN: laccase.

* * *

mono·phe·nol mono·oxy·gen·ase (mon″o-feґnol mon″o-okґsĭ-jən-ās″) [EC 1.14.18.1] any of a group of enzymes of the oxidoreductase class that catalyze the hydroxylation of tyrosine to dopa and the oxidation of dopa to dopaquinone. They are copper proteins that also act on catechols and substituted catechols (i.e., act as catechol oxidases). The reaction is a step in the formation of melanin pigments from tyrosine. Cf. catechol oxidase.

Medical dictionary. 2011.

Look at other dictionaries:

  • monophenol monooxygenase — noun The enzyme tyrosinase …   Wiktionary

  • monophenol oxidase — SYN: monophenol monooxygenase (1) …   Medical dictionary

  • Tyrosinase — monophenol monooxygenase Identifiers EC number 1.14.18.1 CAS number 9002 10 2 …   Wikipedia

  • List of EC numbers (EC 1) — This list contains a list of EC numbers for the first group, EC 1, oxidoreducatases, placed in numerical order as determined by the Nomenclature Committee of the International Union of Biochemistry and Molecular Biology.EC 1.1 Acting on the CH OH …   Wikipedia

  • tyrosinase — SYN: monophenol monooxygenase (1). * * * ty·ros·i·nase tə räs ə .nās, tī , .nāz n an enzyme that promotes the oxidation of phenols (as tyrosine) and is widespread in plants and animals * * * ty·ro·sin·ase (ti roґsin ās) a monophenol… …   Medical dictionary

  • catechol oxidase — cat·e·chol ox·i·dase (katґə kol okґsĭ dās) [EC 1.10.3.1] any of a group of enzymes of the oxidoreductase class that catalyze the oxidation of catechols to 1,2 benzoquinones. They are copper containing proteins that act also upon… …   Medical dictionary

  • Polyphenol oxidase — Identifiers EC number 1.14.18.1 CAS number 9002 10 2 …   Wikipedia

  • Tyrosinase — La tyrosinase (ou catéchol oxydase) est une enzyme qui catalyse l oxydation des phénols (comme la tyrosine) et elle est très répandue parmi les plantes, les animaux et les mycètes. Une personne ayant un gène de tyrosinase mutée est atteinte d… …   Wikipédia en Français

  • Copper deficiency — Classification and external resources ICD 10 E61.0 ICD 9 275.1 Copper deficiency is a very ra …   Wikipedia

  • tyrosinase — noun An enzyme, similar to catechol oxidase, that catalyzes the production of phenolic pigments such as melanin. Syn: monophenol monooxygenase …   Wiktionary