Direct inhibition of brain sepiapterin reductase by a catecholamine and an indoleamine.
Dyspropterin, an intermediate formed from dihydroneopterin triphosphate in the biosynthetic pathway of tetrahydrobiopterin.
Tetrahydrobiopterin biosynthesis. Studies with specifically labeled (2H)NAD(P)H and 2H2O and of the enzymes involved.
Isomerization of 6-lactoyl tetrahydropterin by sepiapterin reductase.
New inhibitors of sepiapterin reductase. Lack of an effect of intracellular tetrahydrobiopterin depletion upon in vitro proliferation of two human cell lines.
The pathway from GTP to tetrahydrobiopterin: three-dimensional structures of GTP cyclohydrolase I and 6-pyruvoyl tetrahydropterin synthase.
The 1.25 A crystal structure of sepiapterin reductase reveals its binding mode to pterins and brain neurotransmitters.
Biosynthesis of pteridines. NMR studies on the reaction mechanisms of GTP cyclohydrolase I, pyruvoyltetrahydropterin synthase, and sepiapterin reductase.
Sepiapterin reductase producing L-threo-dihydrobiopterin from Chlorobium tepidum.
Functionally important residues tyrosine-171 and serine-158 in sepiapterin reductase.
Tetrahydrobiopterin biosynthesis, regeneration and functions.
Role of the conserved Ser-Tyr-Lys triad of the SDR family in sepiapterin reductase.
This enzyme belongs to the short-chain dehydrogenase/reductase (SDR) superfamily, along with Drosophia alcohol dehydrogenase (S00319 in EzCatDB). This enzyme has got a catalytic triad composed of conserved residues, Ser, Tyr, and Lys. The conformation of these residues, compared to that of the NAD molecule, seems to be similar to that of the homologous enzymes. Thus, its catalytic mechanism must be similar to those of the homologous enzymes. According to the literature [7] and [11], this enzyme catalyzes three reactions, including the two reduction steps for the diketo substrate (C03684), as follows: (A) Reduction of C1'-keto group of the substrate by NADPH, forming 1'-hydroxyl intermediate (I00093): (B) Isomerization of 1'-hydroxyl intermediate, forming 1'-keto-2'hydroxyl intermediate (I00094): (C) Reduction of C1'-keto group of the intermediate by NADPH: The first and last reactions must be catalyzed by the catalytic triad, as in the other homologous enzymes.