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Related to tyrosinase: tyrosine


 (tī-rŏs′ə-nās′, -nāz′)
Any of a family of copper-containing enzymes found in animal and plant tissues, fungi, and bacteria, that catalyze the oxidation of phenolic compounds and are responsible for production of the pigment melanin from tyrosine and for the browning of fruits, vegetables, and mushrooms when cut and exposed to air.


(ˌtaɪrəʊsɪˈneɪz; ˌtɪrəʊ-)
(Biochemistry) an enzyme occurring in many organisms that is a catalyst in the conversion of tyrosine to the pigment melanin; inactivity of this enzyme results in albinism


(ˈtaɪ roʊ sɪˌneɪs, -ˌneɪz, ˈtɪr oʊ-)

an enzyme of plant and animal tissues that catalyzes the aerobic oxidation of tyrosine into melanin and other pigments.
[< French (1896); see tyrosine, -ase]
References in periodicals archive ?
A: It takes 12-16 weeks in some cases to see the effects of tyrosinase inhibitors.
The binding of melanocyte-stimulating hormone to the melanocortin 1 receptor sets in motion melanogenesis by activating tyrosinase in melanocytes.
Laccase and Tyrosinase activity was induced 142% and 166 % respectively.
16 It inhibits melanin synthesis by inhibiting L-DOPA to interact with tyrosinase in the process of melanin production.
Antioxidant (DPPH radical scavenging, reducing power (CUPRAC and FRAP), phosphomolybdenum and metal chelating (ferrozine method)) and enzyme inhibitory activities (cholinesterase (Elmann's method), tyrosinase (dopachrome method), [alpha]-amylase (iodine/potassium iodide method) and [alpha]-glucosidase (chromogenic PNPG method)) determined by the method described by Zengin et al.
66,67] During melanogenesis, tyrosinase is responsible for the conversion of L-tyrosine to L-DOPA and subsequently to dopaquinone, then the pathway bifurcates to produce eumelanin or phaeomelanin.
It inhibits tyrosinase, the main pigment forming enzyme.
In the previous works, the leaf extract of mangosteen was found to stimulate melanin synthesis and enhance tyrosinase activity [1] while its stem-bark extract showedcytotoxic activity against colon cancer cells [2].
4,5] have shown that cultured human melanocytes express oestrogen receptors and estradiol increases the levels of tyrosinase, tyrosinase-related-protein 1 and 2, the enzymes involved in human eumelanogenesis within normal human melanocytes.
Autoimmune hypothesis is the most widely accepted, because autoantibodies to melanocytes and tyrosinase have been demonstrated and owing to the usual association of vitiligo with other autoimmune diseases.
Expression of tyrosinase was revealed in some of these cells by dopa reaction.