Kynurenine 3-monooxygenase

Kynurenine 3- monooxygenase ( KMO ) is called the one enzyme that catalyzes the hydroxylation of kynurenine to 3 - hydroxykynurenine. This reaction is a sub-step in the catabolism of the amino acid tryptophan, and the synthesis of NAD and neurologically active substances. KMO is found in animals and some bacteria and fungi. In humans, it is located in larger amounts in liver, placenta, and in the immune system, where it is anchored in the membrane of the mitochondria and protrudes into the cytosol. KMO is target in neurodegenerative diseases, since its inhibition increases the amount of the neuroprotective NMDA receptor antagonist kynurenine.

Upregulation of KMO in pneumokokkaler meningitis and subsequent accumulation of neurotoxic 3- hydroxykynurenine contribute to the neurological damage in by this infectious disease. With cerebral malaria -infected mice lived three times as long if their KMO was inhibited. A role in Huntington's disease is discussed.

Catalyzed reaction

NADPH O2 NADP H2O

L- kynurenine is reacted under consumption of NADPH and oxygen to form 3-hydroxy- L- kynurenine.

Protein isoform Human Genome Organisation Receptor antagonist Huntington's disease Digital Object Identifier PubMed Central
493486
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