Which enzyme is responsible for the breakdown of phenylalanine in the body, and its deficiency leads to phenylketonuria?

A Tyrosinase
B Phenylalanine hydroxylase ✓
C Homogentisate 1,2-dioxygenase
D Cystathionine beta-synthase

Explanation

Phenylalanine hydroxylase is the enzyme responsible for converting phenylalanine to tyrosine, and its deficiency leads to the accumulation of phenylalanine, causing phenylketonuria.

Mnemonic

Phe = Phenylalanine, Hydroxylase = Hydroxy group addition

Source

NCERT Class 12 Biochemistry
Enzymes in Disease Biochemistry Amino Acid Metabolism Medium NURSING Confidence: high