Phenylthiourea is a chemical compound with the formula C6H5NCS, used historically in scientific research as an inhibitor of tyrosinase activity, but now mostly replaced by other more specific agents, and infrequently used in certain diagnostic tests or as a reagent in organic synthesis.
An enzyme of the oxidoreductase class that catalyzes the reaction between L-tyrosine, L-dopa, and oxygen to yield L-dopa, dopaquinone, and water. It is a copper protein that acts also on catechols, catalyzing some of the same reactions as CATECHOL OXIDASE. EC 1.14.18.1.
Insoluble polymers of TYROSINE derivatives found in and causing darkness in skin (SKIN PIGMENTATION), hair, and feathers providing protection against SUNBURN induced by SUNLIGHT. CAROTENES contribute yellow and red coloration.