General Stability | Organism |
---|---|
bovine serum albumin stabilizes | Equus caballus |
NADP+ stabilizes | Equus caballus |
Inhibitors | Comment | Organism | Structure |
---|---|---|---|
2,4-dinitrophenol | 37% inhibition of the reductive reaction at 0.01 mM; slight | Equus caballus | |
2,4-dinitrophenol | - |
Rattus norvegicus | |
6,7-Diethylpterin-H2 | - |
Equus caballus | |
6,7-dimethyldihydropterin | 0.05 mM: 70% inhibition | Equus caballus | |
6,7-dimethyllumazine | slight | Equus caballus | |
6,7-dimethylpterin | 0.05 mM: 46% inhibition; 46% inhibition of the reductive reaction at 0.05 mM | Equus caballus | |
6,7-dimethylpterin-H2 | 70% inhibition of the reductive reaction at 0.05 mM | Equus caballus | |
6-Carboxypterin | 77% inhibition of the reductive reaction at 0.05 mM; IC50 0.014 mM, 0.05 mM: 77% inhibition | Equus caballus | |
6-Carboxypterin | - |
Rattus norvegicus | |
6-Hydroxymethylpterin | 0.05 mM: 23% inhibition; 23% inhibition of the reductive reaction at 0.05 mM | Equus caballus | |
6-methyldihydropterin | 0.05 mM: 59% inhibition | Equus caballus | |
6-methylpterin | 10% inhibition of the reductive reaction at 0.05 mM; slight | Equus caballus | |
6-Methylpterin-H2 | 59% inhibition of the reductive reaction at 0.05 mM | Equus caballus | |
7-Methylpterin | 0.05 mM: 18% inhibition; 18% inhibition of the reductive reaction at 0.05 mM | Equus caballus | |
acetic acid | IC50 0.45 mM, pH 6.5 | Equus caballus | |
benzoic acid | 0.03 mM: 40% inhibition; 40% inhibition of the reductive reaction at 0.03 mM | Equus caballus | |
biopterin | 0.05 mM: 24% inhibition; 24% inhibition of the reductive reaction at 0.05 mM | Equus caballus | |
biopterin-H2 | 31% inhibition of the reductive reaction at 0.05 mM | Equus caballus | |
D,L-Lactic acid | 0.03 mM, 20% inhibition | Equus caballus | |
D-erythro-neopterin | 14% inhibition of the reductive reaction at 0.05 mM | Equus caballus | |
D-erythro-neopterin-H2 | 7% inhibition of the reductive reaction at 0.05 mM | Equus caballus | |
dihydrobiopterin | 0.05 mM: 31% inhibition | Equus caballus | |
dihydrobiopterin | - |
Rattus norvegicus | |
dihydroxanthopterin | slight | Equus caballus | |
DL-lactic acid | 20% inhibition of the reductive reaction at 0.03 mM | Equus caballus | |
formic acid | slight | Equus caballus | |
iodoacetate | 72% inhibition of the reductive reaction at 0.1 mM | Equus caballus | |
Isosepiapterin | 83% inhibition of the reductive reaction at 0.05 mM; IC50 0.0065 mM, 0.05 mM: 83% inhibition | Equus caballus | |
Isoxanthopterin | 0.05 mM: very slight | Equus caballus | |
KCN | 25% inhibition of the reductive reaction at 2.5 mM; slight | Equus caballus | |
L-erythro-dihydroneopterin | 0.05 mM: 29% inhibition, D-isomer: slight inhibition | Equus caballus | |
L-Erythro-neopterin | 0.05 mM: 21% inhibition, D-isomer: slight inhibition; 21% inhibition of the reductive reaction at 0.05 mM | Equus caballus | |
L-Erythro-neopterin-H2 | 29% inhibition of the reductive reaction at 0.05 mM | Equus caballus | |
Leucopterin | 0.05 mM: 21% inhibition; 21% inhibition of the reductive reaction at 0.05 mM | Equus caballus | |
monoiodoacetate | - |
Equus caballus | |
additional information | other unconjugated pteridines, e.g. xanthopterin, that cause slight inhibition of enzymatic reduction | Equus caballus | |
n-butyric acid | IC50 0.032 mM, pH 6.5 | Equus caballus | |
N-ethylmaleimide | - |
Equus caballus | |
n-valeric acid | IC50 0.25 mM, pH 6.5 | Equus caballus | |
NADPH | above 0.1 mM | Equus caballus | |
NaN3 | 15% inhibition of the reductive reaction at 5 mM; slight | Equus caballus | |
NEM | 35% inhibition of the reductive reaction at 0.1 mM, 88% at 1 mM | Equus caballus | |
p-chloromercuribenzoate | - |
Equus caballus | |
PCMB | 93% inhibition of the reductive reaction at 0.01 mM | Equus caballus | |
Propionamide | 0.03 mM, 14% inhibition; 14% inhibition of the reductive reaction at 0.03 mM | Equus caballus | |
propionic acid | 43% inhibition of the reductive reaction at 0.03 mM; IC50 0.0045 mM, pH 6.5 | Equus caballus | |
pterin | 0.05 mM: 18% inhibition; 18% inhibition of the reductive reaction at 0.05 mM | Equus caballus | |
Pyruvic acid | 9% inhibition of the reductive reaction at 0.03 mM; slight | Equus caballus | |
sepiapterin | above 0.05 mM | Equus caballus | |
sepiapterin | - |
Rattus norvegicus | |
Sodium acetate | - |
Equus caballus | |
Xanthopterin | slight | Equus caballus | |
Xanthopterin B2 | slight | Equus caballus | |
Xanthopterin-B2 | 12% inhibition of the reductive reaction at 0.05 mM | Equus caballus | |
xanthopterin-H2 | 9% inhibition of the reductive reaction at 0.05 mM | Equus caballus |
KM Value [mM] | KM Value Maximum [mM] | Substrate | Comment | Organism | Structure |
---|---|---|---|---|---|
additional information | - |
additional information | kinetics | Equus caballus | |
0.0014 | - |
NADPH | pH 10.4, 25°C | Equus caballus | |
0.0021 | - |
sepiapterin | pH 10.4, 25°C | Equus caballus | |
0.0057 | - |
NADP+ | pH 10.4, 25°C | Equus caballus | |
0.0077 | - |
7,8-dihydrobiopterin | pH 10.4, 25°C | Equus caballus | |
0.014 | - |
NADPH | - |
Equus caballus | |
0.021 | - |
sepiapterin | - |
Equus caballus | |
0.057 | - |
dihydrobiopterin | at pH 10.4 | Equus caballus | |
0.077 | - |
NADP+ | at pH 10.4 | Equus caballus |
Localization | Comment | Organism | GeneOntology No. | Textmining |
---|---|---|---|---|
cytoplasm | 92% of total activity | Equus caballus | 5737 | - |
additional information | intracellular localization, overview | Equus caballus | - |
- |
Natural Substrates | Organism | Comment (Nat. Sub.) | Natural Products | Comment (Nat. Pro.) | Rev. | Reac. |
---|---|---|---|---|---|---|
6-(S)-lactoyl-7,8-dihydropterin + NADPH | Rattus norvegicus | equilibrium lies much in favor of dihydrobiopterin formation | 6-(L-erythro-1',2'-dihydroxypropyl)-7,8-dihydropterin + NADP+ | - |
r | |
6-(S)-lactoyl-7,8-dihydropterin + NADPH | Equus caballus | equilibrium lies much in favor of dihydrobiopterin formation | 6-(L-erythro-1',2'-dihydroxypropyl)-7,8-dihydropterin + NADP+ | - |
r | |
6-(S)-lactoyl-7,8-dihydropterin + NADPH | Rattus norvegicus | reverse reaction, L-erythro and L-threo-dihydroneopterin are also oxidized, the corresponding D-isomers are inactive | 6-(L-erythro-1',2'-dihydroxypropyl)-7,8-dihydropterin + NADP+ | - |
r | |
6-(S)-lactoyl-7,8-dihydropterin + NADPH | Equus caballus | reverse reaction, L-erythro and L-threo-dihydroneopterin are also oxidized, the corresponding D-isomers are inactive | 6-(L-erythro-1',2'-dihydroxypropyl)-7,8-dihydropterin + NADP+ | - |
r | |
sepiapterin + NADPH + H+ | Equus caballus | - |
7,8-dihydrobiopterin + NADP+ | - |
r |
Organism | UniProt | Comment | Textmining |
---|---|---|---|
Equus caballus | - |
- |
- |
Rattus norvegicus | - |
- |
- |
Rattus norvegicus | - |
female and male Wistar rats | - |
Purification (Comment) | Organism |
---|---|
liver | Equus caballus |
native enzyme 5000fold from liver by ammonium sulfate and protamine sulfate fractionation, and two times treatment by hydroxylapatite and anion exchange chromatography | Equus caballus |
Source Tissue | Comment | Organism | Textmining |
---|---|---|---|
blood | - |
Rattus norvegicus | - |
blood | - |
Equus caballus | - |
brain | - |
Rattus norvegicus | - |
erythrocyte | - |
Rattus norvegicus | - |
erythrocyte | - |
Equus caballus | - |
heart | - |
Rattus norvegicus | - |
kidney | - |
Rattus norvegicus | - |
liver | - |
Rattus norvegicus | - |
liver | - |
Equus caballus | - |
additional information | tissue distribution, no activity in stomach, small intestine, and muscle, overview | Rattus norvegicus | - |
spleen | - |
Rattus norvegicus | - |
testis | - |
Rattus norvegicus | - |
Specific Activity Minimum [µmol/min/mg] | Specific Activity Maximum [µmol/min/mg] | Comment | Organism |
---|---|---|---|
additional information | - |
purified enzyme | Equus caballus |
Storage Stability | Organism |
---|---|
-15°C, in 150 mM Tris-HCl buffer, pH 6.0, second hydroxylapatite fraction, for 1 week, relatively little loss of activity | Equus caballus |
-15°C, purified enzyme, 0.01 M potassium phosphate buffer, pH 6.0, stable for 1 week with little loss of activity | Equus caballus |
Substrates | Comment Substrates | Organism | Products | Comment (Products) | Rev. | Reac. |
---|---|---|---|---|---|---|
6-(S)-lactoyl-7,8-dihydropterin + NADPH | in the reverse reaction, L-erythro and L-threo-dihydroneopterin are also oxidized, the corresponding L-isomers are inactive | Rattus norvegicus | 6-(L-erythro-1',2'-dihydroxypropyl)-7,8-dihydropterin + NADP+ | - |
r | |
6-(S)-lactoyl-7,8-dihydropterin + NADPH | in the reverse reaction, L-erythro and L-threo-dihydroneopterin are also oxidized, the corresponding L-isomers are inactive | Equus caballus | 6-(L-erythro-1',2'-dihydroxypropyl)-7,8-dihydropterin + NADP+ | - |
r | |
6-(S)-lactoyl-7,8-dihydropterin + NADPH | equilibrium lies much in favor of dihydrobiopterin formation | Rattus norvegicus | 6-(L-erythro-1',2'-dihydroxypropyl)-7,8-dihydropterin + NADP+ | - |
r | |
6-(S)-lactoyl-7,8-dihydropterin + NADPH | equilibrium lies much in favor of dihydrobiopterin formation | Equus caballus | 6-(L-erythro-1',2'-dihydroxypropyl)-7,8-dihydropterin + NADP+ | - |
r | |
6-(S)-lactoyl-7,8-dihydropterin + NADPH | reverse reaction, L-erythro and L-threo-dihydroneopterin are also oxidized, the corresponding D-isomers are inactive | Rattus norvegicus | 6-(L-erythro-1',2'-dihydroxypropyl)-7,8-dihydropterin + NADP+ | - |
r | |
6-(S)-lactoyl-7,8-dihydropterin + NADPH | reverse reaction, L-erythro and L-threo-dihydroneopterin are also oxidized, the corresponding D-isomers are inactive | Equus caballus | 6-(L-erythro-1',2'-dihydroxypropyl)-7,8-dihydropterin + NADP+ | - |
r | |
isosepiapterin + NADPH | - |
Equus caballus | 6-(1-hydroxypropyl)-dihydropterin + NADP+ | - |
? | |
isosepiapterin + NADPH | - |
Equus caballus | ? + NADP+ | - |
r | |
L-erythro-dihydroneopterin + NADP+ | D-isomer completely inactive | Equus caballus | ? | - |
r | |
L-erythro-dihydroneopterin + NADP+ | very slow activity, no activity with the D-isomer | Equus caballus | ? | - |
r | |
L-threo-dihydroneopterin + NADP+ | D-isomer completely inactive | Equus caballus | ? | - |
r | |
L-threo-dihydroneopterin + NADP+ | very slow activity, no activity with the D-isomer | Equus caballus | ? | - |
r | |
additional information | not: 6-acetyl-7-methyldihydropterin | Rattus norvegicus | ? | - |
? | |
additional information | not: 6-acetyl-7-methyldihydropterin | Equus caballus | ? | - |
? | |
additional information | no activity with 6-acetyl-7-methyl-7,8-dihydropterin | Equus caballus | ? | - |
? | |
sepiapterin + NADPH + H+ | - |
Rattus norvegicus | 7,8-dihydrobiopterin + NADP+ | - |
r | |
sepiapterin + NADPH + H+ | - |
Equus caballus | 7,8-dihydrobiopterin + NADP+ | - |
r | |
xanthopterin B2 + NADPH | - |
Equus caballus | 6-(1',2'-dihydroxypropyl)-dihydrolumazine + NADP+ | - |
? | |
xanthopterin-B2 + NADPH | - |
Equus caballus | ? + NADP+ | - |
r |
Synonyms | Comment | Organism |
---|---|---|
SR | - |
Rattus norvegicus |
SR | - |
Equus caballus |
Temperature Optimum [°C] | Temperature Optimum Maximum [°C] | Comment | Organism |
---|---|---|---|
25 | - |
assay at | Rattus norvegicus |
25 | - |
assay at | Equus caballus |
pH Optimum Minimum | pH Optimum Maximum | Comment | Organism |
---|---|---|---|
5.5 | - |
in potassium phosphate buffer | Rattus norvegicus |
5.5 | - |
in potassium phosphate buffer | Equus caballus |
5.5 | - |
for reduction of sepiapterin | Equus caballus |
6.4 | - |
substrate reduction reaction, assay at | Rattus norvegicus |
6.4 | - |
substrate reduction reaction, assay at | Equus caballus |
10.4 | - |
the reverse reaction, oxidation of 7,8-dihydrobiopterin, activity rises with rise of pH | Equus caballus |
10.4 | - |
substrate oxidation reaction, assay at | Rattus norvegicus |
10.4 | - |
substrate oxidation reaction, assay at | Equus caballus |
pH Stability | pH Stability Maximum | Comment | Organism |
---|---|---|---|
5.5 | - |
unstable | Rattus norvegicus |
5.5 | - |
unstable | Equus caballus |
5.5 | - |
pH 6.4 for enzyme assay | Equus caballus |
Cofactor | Comment | Organism | Structure |
---|---|---|---|
NAD+ | reverse reaction, one-fifth of that with NADP+ | Equus caballus | |
NADH | - |
Rattus norvegicus | |
NADH | activity one-fourth of that with NADPH | Equus caballus | |
NADP+ | - |
Rattus norvegicus | |
NADP+ | - |
Equus caballus | |
NADPH | - |
Rattus norvegicus | |
NADPH | - |
Equus caballus |
IC50 Value | IC50 Value Maximum | Comment | Organism | Inhibitor | Structure |
---|---|---|---|---|---|
0.0045 | - |
IC50 0.0045 mM, pH 6.5 | Equus caballus | propionic acid | |
0.0065 | - |
IC50 0.0065 mM, 0.05 mM: 83% inhibition | Equus caballus | Isosepiapterin | |
0.014 | - |
IC50 0.014 mM, 0.05 mM: 77% inhibition | Equus caballus | 6-Carboxypterin | |
0.032 | - |
IC50 0.032 mM, pH 6.5 | Equus caballus | n-butyric acid | |
0.25 | - |
IC50 0.25 mM, pH 6.5 | Equus caballus | n-valeric acid | |
0.45 | - |
IC50 0.45 mM, pH 6.5 | Equus caballus | acetic acid |