Like the other aromatic amino acid hydroxylases (AAAHs), tyrosine hydroxylase use the cofactor tetrahydrobiopterin (BH4) under normal conditions, although other similar molecules may also work as a cofactor for tyrosine hydroxylase.
Tyrosine hydroxylase operates like other aromatic amino acid hydroxylases (AAAHs), using tetrahydrobiopterin (BH4) as its cofactor under normal conditions, and similar molecules might also function as a cofactor for tyrosine hydroxylase.