Reaction catalyzed by tyrosine 3-monooxygenase (1.14.16.2)
+
+
=
+
L-tyrosine
+
5,6,7,8,-tetrahydro-L-biopterin
+
O2
=
3,4-dihydroxy-L-phenylalanine
+
4a-hydroxytetrahydro-L-biopterin
