Metabolites of tryptophan can give rise to all of the following except

Phenylketouria is due to deficiency of phenylalanine hydroxylase enzyme. This enzyme catalyzes hydroxylation of aromatic side chain of phenylalanine to generate tyrosine. The conversation of phenylalanine to tyrosine is blocked resulting in the excretion of high amounts of PHENYLPYRUVATE in urine. Clinical features:- mental retardation , failure to talk or walk , seizures, tremors.