Kynureninase is a pyridoxal-5'-phosphate (pyridoxal-P) dependent enzyme that catalyzes the cleavage of L-kynurenine and L-3-hydroxykynurenine into anthranilic and 3-hydroxyanthranilic acids, respectively. Kynureninase is involved in the biosynthesis of NAD cofactors from tryptophan through the kynurenine pathway. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Nov 2010]
Function:
Catalyzes the cleavage of L-kynurenine (L-Kyn) and L-3-hydroxykynurenine (L-3OHKyn) into anthranilic acid (AA) and 3-hydroxyanthranilic acid (3-OHAA), respectively. Has a preference for the L-3-hydroxy form. Also has cysteine-conjugate-beta-lyase activity.
Subcellular Location:
Cytoplasm.
Tissue Specificity:
Expressed in all tissues tested (heart, brain placenta, lung, liver, skeletal muscle, kidney and pancreas). Highest levels found in placenta, liver and lung. Expressed in all brain regions.
DISEASE:
Note=Xanthurenic aciduria manifesting as massive urinary excretion of large amounts of kynurenine, 3-hydroxykynurenine and xanthurenic acid has been observed in an individual carrying a homozygous missense change in KYNU (PubMed:17334708). The urinary pattern in the patient suggests kynureninase deficiency and a block in the conversion of kynurenine and 3-hydroxykynurenine to anthranilate and 3-hydroxyanthranilate, respectively.
Similarity:
Belongs to the kynureninase family.
SWISS:
Q16719
Gene ID:
8942
Database links:
Entrez Gene: 8942 Human
Entrez Gene: 70789 Mouse
Entrez Gene: 116682 Rat
Omim: 605197 Human
SwissProt: Q16719 Human
SwissProt: Q9CXF0 Mouse
SwissProt: P70712 Rat
Unigene: 470126 Human
Unigene: 105278 Mouse
Unigene: 10575 Rat
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