Study of the kinetics of oxidation of monophenols by tyrosinase. The effect of reducers.
Kinetics of oxidation of monophenols by tyrosinase from the fungus Aspergillus flavipes 56003 and the effect of Fe2+, serine, and ascorbic acid on this reaction were studied. The effectors were shown to accelerate the oxidation of monophenols, decreasing the lag-time of the reaction. It is assumed that the activation of the tyrosinase in the presence of Fe2+ is due to a direct reduction of the active site copper ions. Serine and ascorbic acid are supposed to affect the reaction of quinone transformation. The activation of the enzyme in the presence of Fe2+ suggests that the oxidation of monophenols is an autocatalytic process.
Gukasyan
G S
GS
Armenian Scientific Research Institute of Applied Chemistry (ARIAC), Yerevan, 375029 Armenia. bio@arminco.com
D001205:Ascorbic Acid / Q000494:pharmacology; D001231:Aspergillus flavus / Q000201:enzymology; D004789:Enzyme Activation; D007501:Iron / Q000494:pharmacology; D007700:Kinetics; D014442:Monophenol Monooxygenase / Q000378:metabolism* / Q000494:pharmacology; D010084:Oxidation-Reduction; D010100:Oxygen / Q000378:metabolism; D010636:Phenols / Q000378:metabolism*; D012694:Serine / Q000494:pharmacology; D014443:Tyrosine / Q000378:metabolism
D010636:Phenols; D014443:Tyrosine; D012694:Serine; D007501:Iron; D014442:Monophenol Monooxygenase; D001205:Ascorbic Acid; D010100:Oxygen