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Updated: Aug 11, 2026

Simultaneous Quantification of Selected Kynurenines Analyzed by Liquid Chromatography-Mass Spectrometry in Medium Collected from Cancer Cell Cultures
Published on: May 9, 2020
Familial hypertryptophanemia, tryptophanuria and indoleketonuria
Abstract:
Two patients presenting with mental subnormality and severe emotional lability were examined for possible inborn errors of metabolism. Amino acid and organic acid analyses of their plasma and urine revealed a novel and grossly abnormal metabolism of tryptophan. Basal levels of plasma tryptophan were ten times that of controls and the 24-hour urinary excretion of tryptophan was up to 50 times greater than normal. Both patients excreted about 100 times the normal amounts of indoleacetic, indolelactic and indolepyruvic acids. Administration of oral antibiotic to one of the patients to eliminate intestinal bacteria did not result in any reduction in the excretion of the indoleic acids. The results are interpreted in terms of a possible congenital defect in the normal conversion of tryptophan to kynurenine.
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Related Concept Videos
Translation
Translation is the process of synthesizing proteins from the genetic information carried by messenger RNA (mRNA). Following transcription, it constitutes the final step in the expression of genes. This process is carried out by ribosomes, complexes of protein and specialized RNA molecules. Ribosomes, transfer RNA (tRNA), and other proteins produce a chain of amino acids—the polypeptide—as the end product of translation.
Translation Produces the Building Blocks of Life
Translation
Translation is the process of synthesizing proteins from the genetic information carried by messenger RNA (mRNA). Following transcription, it constitutes the final step in the expression of genes. This process is carried out by ribosomes, complexes of protein and specialized RNA molecules. Ribosomes, transfer RNA (tRNA), and other proteins produce a chain of amino acids—the polypeptide—as the end product of translation.
Translation Produces the Building Blocks of Life
Inborn Errors of Metabolism
Pharmacogenetics of Phase II Enzymes: N-acetyltransferase, Thiopurine S-methyltransferase, UDP-glucuronosyltransferase
Amino Acid Biosynthetic Pathways
Repressible Operon: trp Operon