dihydroneopterin-triphosphate has been researched along with tetrahydropterin* in 2 studies
2 other study(ies) available for dihydroneopterin-triphosphate and tetrahydropterin
| Article | Year |
|---|---|
1H-NMR and mass spectrometric studies of tetrahydropterins. Evidence for the structure of 6-pyruvoyl tetrahydropterin, an intermediate in the biosynthesis of tetrahydrobiopterin.
The conversion of dihydroneopterin triphosphate in the presence of 6-pyruvoyl tetrahydropterin synthase was followed by 1H-NMR spectroscopy. The interpretation of the spectra of the product is unequivocal: they show formation of a tetrahydropterin system carrying a stereospecifically oriented substituent at the asymmetric C(6) atom. The spectra are compatible with formation of a (3')-CH3 function, and with complete removal of the 1' and 2' hydrogens of dihydroneopterin triphosphate. The fast-atom-bombardment/mass spectrometry study of the same product yields a [M + H]+ ion at m/z 238 compatible with the structure of 6-pyruvoyl tetrahydropterin. The data support the proposed structure of 6-pyruvoyl tetrahydropterin as a key intermediate in the biosynthesis of tetrahydrobiopterin. Topics: Alcohol Oxidoreductases; Biopterins; Magnetic Resonance Spectroscopy; Mass Spectrometry; Models, Chemical; Neopterin; Oxidation-Reduction; Phosphorus-Oxygen Lyases; Pteridines; Pterins; Stereoisomerism | 1990 |
Biosynthesis of tetrahydrobiopterin: conversion of dihydroneopterin triphosphate to tetrahydropterin intermediates.
It is known that the first step in the de novo synthesis of tetrahydrobiopterin from GTP is the conversion of GTP to dihydroneopterin triphosphate. Recent evidence supports the conclusion that beyond this first step, the pterin intermediates in the pathway are all at the tetrahydro level of reduction. We have now shown that partially purified fractions from rat liver, rat brain and bovine adrenal medulla catalyze the conversion of dihydroneopterin triphosphate to tetrahydrobiopterin, as well as to the putative intermediates in the pathway, 6-pyruvoyl-tetrahydropterin and 6-lactoyl-tetrahydropterin. Results of both enzymatic and chemical studies support the assigned structures for the latter two tetrahydropterins. We have also purified extensively from brain an enzyme, distinct from sepiapterin reductase, that catalyzes the TPNH-dependent reduction of 6-pyruvoyl-tetrahydropterin to 6-lactoyl-tetrahydropterin. The role of this reductase in tetrahydrobiopterin synthesis has not yet been established. Topics: Adrenal Medulla; Animals; Biopterins; Brain; Cattle; Chemical Phenomena; Chemistry; In Vitro Techniques; Kinetics; Liver; Neopterin; Pteridines; Pterins; Rats | 1985 |