1. What enzyme is most commonly defective in people with phenylketonuria?
The important metabolic enzyme, PAH, is missing from patients with PKU.
2. What reaction does this enzyme catalyze? (What is the substrate and what product is produced?)
Phenylalanine is produced at dangerous levels when this enzyme is catalyzed. It can cause mental retardation and epilepsy.
3. Describe the symptoms of phenylketonuria.
The symptoms of PKU are a smaller than usual head, mental retardation and epilepsy, a musty odor on the skin, and lighter than normal hair and skin.
4. What causes the symptoms of PKU, the lack of a substance or the buildup of one?
Phenylalanine is found in proteins of the food that we eat, and reacts badly with the PKU because the hindered enzyme is one of a metabolic nature.
5. How common is phenylketonuria? How is it treated?
PKU is not very common. Rates in Asian and Caucasians are rare but come up more in Irish and Turkish heritage families. It is treatable and is treated by a low protein diet that is carried out throughout the patient’s lifetime.