4-n-butylresorcinol, a depigmenting agent used in cosmetics, reacts with tyrosinase
| Autor: | Jose Antonio Teruel-Puche, Francisco García-Cánovas, José Tudela, Jose Berna, Antonio Garcia-Jimenez, Carmen Vanessa Ortiz-Ruiz |
|---|---|
| Rok vydání: | 2016 |
| Předmět: |
0301 basic medicine
chemistry.chemical_classification Tyrosinase Clinical Biochemistry Cell Biology Ascorbic acid Biochemistry Medicinal chemistry Catalysis 030207 dermatology & venereal diseases 03 medical and health sciences chemistry.chemical_compound 030104 developmental biology 0302 clinical medicine Enzyme chemistry Docking (molecular) Genetics Thiol Molecule Hydrogen peroxide Molecular Biology |
| Zdroj: | IUBMB Life. 68:663-672 |
| ISSN: | 1521-6543 |
| Popis: | 4-n-Butylresorcinol (BR) is considered the most potent inhibitor of tyrosinase, which is why it is used in cosmetics as a depigmenting agent. However, this work demonstrates that BR is a substrate of this enzyme. The Em (met-tyrosinase) form is not active on BR, but Eox (oxy-tyrosinase) can act on this molecule, hydroxylating it to o-diphenol. In turn, this is oxidized to an o-quinone, which isomerizes to a red p-quinone. Thus, for tyrosinase to act on this compound, a mechanism to generate Eox in the medium is required, which can be achieved by means of hydrogen peroxide or ascorbic acid. A kinetic analysis of the proposed mechanism allows its kinetic characterization: catalytic constant kcatBR (8.49 ± 0.20 s(-1) ) and Michaelis-constant KMBR (60.26 ± 8.76 μM). These findings are compared with those for other monophenolic substrates of tyrosinase. Studies of BR docking to the Em form of the enzyme show that the hydroxyl group in C-1 position is oriented toward the copper atom A (CuA), as in it is L-tyrosine. As regards Eox , BR is oriented with the carbon in C-6 position ready to be hydroxylated. The reaction of BR originates o-quinones, which isomerize to p-quinones, which in turn, could react with thiol compounds, a finding that could have important implications for pharmacology and the cosmetic industry. © 2016 IUBMB Life, 68(8):663-672, 2016. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
Plný text