4-hydroxyphenylpyruvate dioxygenase

4-Hydroxyphenylpyruvate dioxygenase (HPPD) is an enzyme that in humans is encoded by the HPPD gene. This enzyme is part of the phenylalanine metabolic pathway and is significant in the catabolism of tyrosine.

Function

4-Hydroxyphenylpyruvate dioxygenase is a key enzyme in the metabolic pathway of tyrosine, catalyzing the conversion of 4-hydroxyphenylpyruvate to homogentisate. This reaction is one of the steps in the breakdown of tyrosine, an amino acid that is used in the synthesis of proteins.

Clinical significance

Mutations in the HPPD gene can lead to a rare metabolic disorder known as Hawkinsinuria, which is characterized by the excretion of hawkinsin, a metabolite of tyrosine, in the urine. This condition can lead to metabolic acidosis, failure to thrive, and developmental delay.

In addition, inhibitors of 4-hydroxyphenylpyruvate dioxygenase are used as herbicides, as they prevent the synthesis of carotenoids in plants, leading to their death.

See also

• Tyrosine metabolism
• Hawkinsinuria
• Herbicide

References

‎