Dihydrobiopterin

Dihydrobiopterin

Chemical structure of Dihydrobiopterin

Dihydrobiopterin is a naturally occurring compound that plays a crucial role in various biological processes. It is a derivative of the molecule biopterin and is involved in the synthesis of several important neurotransmitters and hormones.

Structure and Function

Dihydrobiopterin, also known as 7,8-dihydrobiopterin, is a pteridine derivative. It consists of a pteridine ring system with a dihydroxypropyl side chain attached at position 6. The chemical structure of dihydrobiopterin is shown in the image on the right.

Dihydrobiopterin acts as a cofactor for the enzyme phenylalanine hydroxylase, which is involved in the conversion of the amino acid phenylalanine to tyrosine. This enzymatic reaction is essential for the normal metabolism of phenylalanine and is crucial for the synthesis of various neurotransmitters, including dopamine, norepinephrine, and epinephrine.

In addition to its role in phenylalanine metabolism, dihydrobiopterin is also involved in the synthesis of nitric oxide (NO). It serves as a cofactor for the enzyme nitric oxide synthase, which catalyzes the production of NO from the amino acid L-arginine. Nitric oxide is a signaling molecule that plays a critical role in various physiological processes, including vasodilation, neurotransmission, and immune response.

Clinical Significance

Mutations in the genes responsible for the synthesis or recycling of dihydrobiopterin can lead to a group of rare genetic disorders known as dihydrobiopterin deficiency or tetrahydrobiopterin deficiency. These disorders are characterized by impaired production of neurotransmitters and hormones, resulting in a range of neurological and metabolic abnormalities.

Individuals with dihydrobiopterin deficiency may experience symptoms such as intellectual disability, movement disorders, seizures, and behavioral problems. Early diagnosis and treatment are crucial to manage the symptoms and prevent long-term complications.

See Also

• Biopterin
• Phenylalanine hydroxylase
• Nitric oxide synthase
• Dihydrobiopterin deficiency
• Tetrahydrobiopterin deficiency