Human afflictions and chromosomal aberrations / Raymond Turpin and Jérôme Lejeune.

  • Turpin, Raymond, 1895-1988. Chromosomes humains. English
Date:
1969
Catalogue details

Licence: Attribution-NonCommercial 4.0 International (CC BY-NC 4.0)

Credit: Human afflictions and chromosomal aberrations / Raymond Turpin and Jérôme Lejeune. Source: Wellcome Collection.

    317/412 (page 301)
    CHROMOSOMh-LI N KI D BIOCHI MICAL EFFECTS 301 -CH,-COOH ■CH2 —CO —COOH CH2—COOH CH2—CHj—NH2 OH Xanthurenic acid COOH ^ 'NH2 OH 3-OH-Kynurenine NH2 3-OH-anthrQnilicacid Nicotinamide^— [nadp,NAd]-^— Nicotinic acid N-methyl-nicotinamide'^ , I Nicotinic acid ribotide Glutaricacid CO2 N-methyl-6-pyrídone » Tronsaminases dependent on Bg Kynureninase dependent on Bg *** Decarboxylase dependent on Bg Fig. 15.4. Scheme of tryptophan metabolism. The results of investigation of tryptophan metabolism in children with tri¬ somy 21 may correspond to this possibility. In the human body 1-3 per cent of exogenous tryptophan is transformed either into serotonin and 5-hydroxyindoleacetic acid (5-HIAA), on the one hand, or into indoleacetic acid (lAA) on the other. The bulk of the tryptophan is cata- bolized by opening of the indole ring giving kynurenine, then by oxidation, for which the enzyme cofactor is NADP, giving 3-hydroxykynurenine. Normally, small quantities of anthranilic, kynurenic and xanthurenic acids form. The bulk of the 3-hydroxykynurenine is catabolized in its turn, giving either nicotinic