Tag: Kynurenine
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Indoleamine-pyrrole 2,3-dioxygenase (IDO or INDO) is involved in tryptophan metabolism
Indoleamine-pyrrole 2,3-dioxygenase (IDO or INDO EC 1.13.11.52) is a heme-containing enzyme physiologically expressed in a number of tissues and cells, such as the small intestine, lungs, female genital tract or placenta. In humans is encoded by the IDO1 gene. IDO is involved in tryptophan metabolism. It is one of three enzymes that catalyze the first and rate-limiting step in the kynurenine pathway, the O2-dependent oxidation of L-tryptophan to N-formylkynurenine, the others being indolamine-2,3-dioxygenase 2 (IDO2) and tryptophan 2,3-dioxygenase…
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Kynureninase or L-Kynurenine hydrolase (KYNU) is part of the pathway for the catabolism of Trp and the biosynthesis of NAD cofactors from tryptophan (Trp).
Kynureninase or L-Kynurenine hydrolase (KYNU) (EC 3.7.1.3) is a PLP dependent enzyme that catalyses the cleavage of kynurenine (Kyn) into anthranilic acid (Ant). It can also act on 3-hydroxykynurenine (to produce 3-hydroxyanthranilate) and some other (3-arylcarbonyl)-alanines. Note: 3-Hydroxykynurenine is a metabolite of tryptophan, which filters UV light in the human lens. It is one of two pigments identified as responsible for the goldenrod crab spider‘s (Misumena vatia) yellow coloration. 3-Hydroxyanthranilic acid is an intermediate in the metabolism of tryptophan. It…
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Ommochrome (visual pigment) and Kynurenine (a metabolite of the amino acid l-tryptophan used in the production of niacin)
Ommochrome (or visual pigment) refers to several biological pigments that occur in the eyes of crustaceans and insects. The eye color is determined by the ommochromes. Ommochromes are also found in the chromatophores of cephalopods, and in spiders. Ommochromes are metabolites of tryptophan, via kynurenine and 3-hydroxykynurenine. They are responsible for a wide variety of colors, ranging from yellow over red and brown to black. Lighter colors tend to be generated by ommatins,…
