Reaction catalyzed by vitamin D3 24-hydroxylase (1.14.15.16)
+
2
reduced adrenodoxin
+
2
+
=
+
2
+
H2O
calcitriol
+
2 reduced adrenodoxin
+
2 H+
+
O2
=
calcitetrol
+
2 oxidized adrenodoxin
+
H2O