Reaction catalyzed by tyrosinase (1.14.18.1)

		+			=			+		H2O
	phaselic acid	+		1/2 O2	=		(2S)-2-[[(2E)-3-(3,4-dioxocyclohexa-1,5-dien-1-yl)prop-2-enoyl]oxy]butanedioic acid	+		H2O