Kynurenine-3-Monooxygenase (KMO)

Kynurenine 3-monooxygenase (KMO; EC 1.14.13.9) is an NADPH-dependent flavin monooxygenase that catalyzes the hydroxylation of the L-tryptophan metabolite L-kynurenine to form L-3-hydroxykynurenine.The predicted 486-amino acid human protein shares 47% sequence identity with Drosophila KMO. When expressed in mammalian cells, recombinant human KMO exhibited kinetic properties similar to those of the native human protein. Northern blot analysis revealed that human KMO is expressed as an approximately 2-kb mRNA in liver and placenta, and at lower levels in kidney.Expression of a mutant huntingtin (HTT) fragment in yeast, as in neurons, results in the formation of inclusion bodies and confers cellular toxicity.