Excretion of phenylpyruvic, 4-hydroxyphenylpyruvic and indolyl-3-acetic acids by the skin fibroblasts from a phenylketonuric child.

High-resolution gas chromatography and mass spectrometry have been used to analyse the changing chemical composition of the culture medium upon the growth of skin fibroblasts from a healthy individual and from a classical phenylketonuric (PKU) patient. The PKU fibroblasts, unlike normal ones, were found to excrete into the culture medium phenylpyruvate, 4-hydroxyphenylpyruvate, indolyl-3-acetate and an unidentified metabolite containing the phenyl group. This testifies to the disturbed metabolism of phenylalanine, tyrosine and tryptophan in the PKU fibroblasts. This seems to be the reason for their reduced viability as compared with normal fibroblasts.