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The phenylthiourea is a competitive inhibitor of the enzymatic oxidation of DOPA by phenoloxidase.

06:00 EDT 4th May 2011 | BioPortfolio

Summary of "The phenylthiourea is a competitive inhibitor of the enzymatic oxidation of DOPA by phenoloxidase."

Phenoloxidase is a key enzyme of melanization catalyzing the oxidation of phenols. Phenylthiourea (PTU) is the well-known and widely used inhibitor of phenoloxidase. However, the mechanism of its action is not quite clear. In the present work, the effect of PTU on the enzymatic oxidation of 3-(3,4-dihydroxyphenyl)-l-alanine (DOPA) by phenoloxidase was studied by spectrophotometric methods. The inhibition constant of PTU was estimated as 0.21 ± 0.09 µM and the competitive type of inhibition was determined for this reaction.

Affiliation

Institute of Chemical Kinetics and Combustion, Laboratory of Chemistry and Physics of Free Radicals, Institutskaya 3, Novosibirsk, Russian Federation.

Journal Details

This article was published in the following journal.

Name: Journal of enzyme inhibition and medicinal chemistry
ISSN: 1475-6374
Pages:

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