Biochemistry : Protein Catabolism Intermediates

Study concepts, example questions & explanations for Biochemistry

varsity tutors app store varsity tutors android store

Example Questions

Example Question #10 : Protein Catabolism

Phenylketonuria is a genetic disorder resulting in a lack of phenylalanine hydroxylase activity. During the first step of phenylalanine metabolism, phenylalanine is hydroxylated into what amino acid?

Possible Answers:

Alanine

Tyrosine

Tryptophan

Serine

Threonine

Correct answer:

Tyrosine

Explanation:

The first step in phenylalanine metabolism is conversion of phenylalanine to tyrosine. Tyrsoine is simply a hydroxylated version of phenylalanine. 

Learning Tools by Varsity Tutors