Showing chemical card for Xanthurenate-8-O-beta-D-glucoside (CFc000008208)
Record Information
Version
1.0
Creation Date
2022-08-28 10:25:12 UTC
Update Date
2022-09-13 18:54:53 UTC
Chemfont ID
CFc000008208
Molecule Identification
Common Name
Xanthurenate-8-O-beta-D-glucoside
Definition
Xanthurenic acid 8-O-beta-D-glucoside, a fluorescent metabolite, has been isolated from heads of eye-color mutants of Drosophila melanogaster. Only a few mutations cause it to accumulate, viz. cardinal (cd), dark red brown (drb), Henna-recessive (Hnr), purple (pr), Punch2 (Pu2), Punch-Grape (PuGr), and scarlet (st). After purification by ion-exchange chromatography, the spectroscopic, chemical, and enzymatic analyses revealed that it is a novel quinoline derivative. Feeding experiments suggest that this glucoside is synthesized from 3-hydroxykynurenine and that free xanthurenic acid is not a precursor. The results from the analysis for its occurrence in double mutants, together with the fact that xanthurenic acid 8-glucoside share the same precursor as xanthurenic acid and xanthommatin, suggest that xanthurenic acid 8-glucoside formation is closely related to the regulation of the last step in the biosynthesis of xanthommatin.[PMID: 3922986 ]. Xanthurenic acid 8-glucoside is a side metabolite of the tryptophan-xanthommatin pathway in Drosophila. From 3-hydroxykynurenine, two biosynthetic pathways can be envisaged, one via xanthurenic acid, and another via 3-O-glucoside of 3-hydroxykynurenine. Evidence is presented to show that the synthesis takes place via xanthurenic acid. (a) the Drosophila melanogaster vermilion purple mutant (unable to synthesize 3-hydroxykynurenine) synthesizes xanthurenic acid 8-glucoside when fed with xanthurenic acid; and (b) the activities required for its synthesis via xanthurenic acid have been found (3-hydroxykynurenine transaminase and xanthurenic acid:UDP-glucosyltransferase). This is the first time that a UDP-glucosyltransferase activity that utilizes xanthurenic acid has been demonstrated. The enzyme in crude extracts from Drosophila sordidula shows the following characteristics. (a) It has optimal activity at 35 degrees C at pH 7.1 (in buffer Tris-HCl), and in the presence of a divalent cation (Mg2+ or Mn2+); (b) the activity is inhibited by xanthurenic acid (above 1.5 mM), UDP, D-gluconic acid 1,5-lactone, and Triton X-100; (c) it is localized in both the microsomal and the soluble fractions; (d) the specific activity is two times higher in heads than in bodies; and (e) the activity is enhanced in flies fed with phenobarbital.
Belongs to the class of organic compounds known as phenolic glycosides. These are organic compounds containing a phenolic structure attached to a glycosyl moiety. Some examples of phenolic structures include lignans, and flavonoids. Among the sugar units found in natural glycosides are D-glucose, L-Fructose, and L rhamnose.
