Which biochemical process involves the conversion of phenylalanine to tyrosine, and is impaired in individuals with phenylketonuria?

A Gluconeogenesis
B Glycolysis
C Pentose phosphate pathway
D Aromatic amino acid hydroxylation ✓

Explanation

The conversion of phenylalanine to tyrosine involves the hydroxylation of phenylalanine, which is impaired in individuals with phenylketonuria due to a deficiency in the enzyme phenylalanine hydroxylase.

Source

Harper's Illustrated Biochemistry, 31st edition
Fundamentals of Biochemistry Metabolic Pathways Amino Acid Metabolism Hard MEDICAL Confidence: high