Studies on Conversion of Phenylalanine to Tyrosine in Phenylpyruvic Oligophrenia.

Abstract

SummaryA homogenate of a biopsy specimen of liver obtained from a patient with phenylpyruvic oligophrenia did not catalyze detectable conversion of phenylalanine to tyrosine, under conditions whereby liver homogenates obtained from normal individuals were active in catalyzing such conversion. Addition of a fraction prepared from rat liver (which exhibited relatively low activity alone) to the inactive phenylketonuric liver homogenate resulted in striking activation of the conversion of phenylalanine to tyrosine.