Phenylalanine as substrate for tyrosine hydroxylase in bovine adrenal chromaffin cells.

نویسندگان

  • M H Fukami
  • J Haavik
  • T Flatmark
چکیده

Incubation of bovine chromaffin cells with L-[14C]phenylalanine resulted in label accumulation in catecholamines at about 30% of the rate seen with L-tyrosine as precursor. Studies with purified tyrosine hydroxylase (EC 1.14.16.2) showed that the enzyme catalysed the hydroxylation of L-phenylalanine first to L-p-tyrosine and then to 3,4-dihydroxyphenylalanine (DOPA). No evidence for a significant involvement of an L-m-tyrosine intermediate in DOPA formation was found.

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عنوان ژورنال:
  • The Biochemical journal

دوره 268 2  شماره 

صفحات  -

تاریخ انتشار 1990