in this study , we have compared the reactivities of o-quinones , derived from tyrosinase oxidation of various catechols , with the cysteine residue in bovine serum albumin . o-quinone forms of dopamine , norepinephrine , n-acetyldopa , n-acetyldopamine , 3,4-dihydroxyphenylacetic acid , pyrocatechol and 4-methylcatechols were much more reactive than dopaquinone , while o-quinone forms of 5-s-cysteinyldopa and epinephrine were much less reactive .
C0010654
cysteine
C0010665
cysteinyldopa