Kynurenine

**Semantic type:** Amino Acid, Peptide, or Protein

**Definition:** A ketone and an amino acid derivative that is synthesized by either tryptophan 2,3-dioxygenase (TDO)- or indoleamine 2,3-dioxygenase (IDO)-mediated oxidation of tryptophan with diverse biological functions, including vasodilatory, immunoregulatory and neuromodulatory activities. Kynurenine is a precursor for niacin. Additionally, kynurenine can be further metabolized into anthranilic acid, kynurenic acid, and 3-hydroxykynurenine; aberrant production of kynurenine is associated with neurological disease-related cognitive deficits and depressive symptoms. Overexpressed in certain cancer cell types, kynurenine could potentially be used as a biomarker to assess cancer risk.

**Synonyms:** - (2S)-2-Amino-4-(2-Aminophenyl)-4-Oxobutanoic Acid - (S)-Kynurenine - 3-Anthraniloyl-L-Alanine - KYN - KYNURENINE - Kynurenine, L- - L-Kynurenine