Phenylalanine hydroxylase

The phenylalanine hydroxylase (PAH ) is the one enzyme that catalyzes the conversion of all living beings in L- phenylalanine to tyrosine. Therefore, it is essential for all eukaryotes, the high levels of phenylalanine in the organism are harmful. PAH is rich in iron and binds tetrahydrobiopterin cofactor. In humans it is mainly within the cytosol ( cytosol ) of liver cells before. Mutations in the PAH gene can be reduced to the lack of activity of the enzyme and corresponding hyperphenylalaninemia even lead to phenylketonuria.

Catalysed reaction equilibrium

O2 ⇔ ⇔

Phenylalanine is oxidized to tyrosine, and vice versa.