Production of 6-hydroxydopa by human tyrosinase.
A tyrosinase obtained from cultured human melanoma cells was found to oxygenate 2,4-dihydroxyphenylalanine to the strongly cytotoxic amino acid 6-hydroxydopa (2,4,5-trihydroxyphenylalanine). The oxygenation was dependent on the presence of a reducing co-substrate such as dopa or dopamine. The rate of oxygenation of 2,4-dihydroxyphenyl-D,L-alanine was similar to that of L-tyrosine, the normal substrate of tyrosinase. The enzymatic reaction demonstrated may prove of value in the chemotherapy of human melanoma.
Hansson
C
C
Rorsman
H
H
Rosengren
E
E
Wittbjer
A
A
D002384:Catalysis; D004156:Catechol Oxidase / Q000378:metabolism*; D002460:Cell Line; D003470:Culture Media; D004295:Dihydroxyphenylalanine / Q000031:analogs & derivatives* / Q000096:biosynthesis / Q000378:metabolism; D006801:Humans; D008545:Melanoma; D014442:Monophenol Monooxygenase / Q000378:metabolism*
D003470:Culture Media; C001388:6-hydroxydopa; D004295:Dihydroxyphenylalanine; D004156:Catechol Oxidase; D014442:Monophenol Monooxygenase