Reaction catalyzed by phenylalanine 4-monooxygenase (1.14.16.1)
+
+
=
+
+
H2O
S-carboxymethyl-L-cysteine
+
tetrahydrobiopterin
+
O2
=
S-carboxymethyl-L-cysteine S-oxide
+
dihydrobiopterin
+
H2O