Activating Compound | Comment | Organism | Structure |
---|---|---|---|
FAD | activates 10fold by addition of 0.004 mM, stabilizes against heat inactivation | Aspergillus nidulans |
Inhibitors | Comment | Organism | Structure |
---|---|---|---|
azide | - |
Aspergillus nidulans | |
cyanide | 99% inhibition at 10 mM | Aspergillus nidulans | |
p-chloromercuribenzoate | reversion of the inhibition by addition of reduced glutathione | Aspergillus nidulans |
KM Value [mM] | KM Value Maximum [mM] | Substrate | Comment | Organism | Structure |
---|---|---|---|---|---|
0.045 | - |
NADPH | + nitrate | Aspergillus nidulans | |
0.2 | - |
nitrate | cosubstrate NADPH | Aspergillus nidulans | |
2.5 | - |
FADH2 | + nitrate | Aspergillus nidulans | |
3 | - |
FMNH2 | + nitrate | Aspergillus nidulans |
Metals/Ions | Comment | Organism | Structure |
---|---|---|---|
Molybdenum | molybdoflavoprotein | Aspergillus nidulans |
Molecular Weight [Da] | Molecular Weight Maximum [Da] | Comment | Organism |
---|---|---|---|
38000 | - |
2 * 59000 + 2 * 38000, SDS-PAGE, after heat-treatment all polypeptide chains are 59 kDa | Aspergillus nidulans |
59000 | - |
2 * 59000 + 2 * 38000, SDS-PAGE, after heat-treatment all polypeptide chains are 59 kDa | Aspergillus nidulans |
180000 | - |
gel filtration, sucrose density gradient | Aspergillus nidulans |
Natural Substrates | Organism | Comment (Nat. Sub.) | Natural Products | Comment (Nat. Pro.) | Rev. | Reac. |
---|---|---|---|---|---|---|
nitrate + NADPH | Aspergillus nidulans | - |
nitrite + NADP+ + H2O | - |
? |
Organism | UniProt | Comment | Textmining |
---|---|---|---|
Aspergillus nidulans | - |
IFO No. 6083 | - |
Purification (Comment) | Organism |
---|---|
ammonium slufate precipitation, ion-exchange, gel filtration, hydroxylapatite column. FAD and EDTA essential in all buffers during purification | Aspergillus nidulans |
Specific Activity Minimum [µmol/min/mg] | Specific Activity Maximum [µmol/min/mg] | Comment | Organism |
---|---|---|---|
15.5 | - |
- |
Aspergillus nidulans |
Storage Stability | Organism |
---|---|
-80°C, 0.02 mM FAD, several months with only slight loss of the activity | Aspergillus nidulans |
Substrates | Comment Substrates | Organism | Products | Comment (Products) | Rev. | Reac. |
---|---|---|---|---|---|---|
nitrate + NADPH | - |
Aspergillus nidulans | nitrite + NADP+ + H2O | - |
? | |
nitrate + NADPH | 4 activities: NADPH-nitrate reductase, FADH-nitrate reductase, reduced methyl viologen-nitrate reductase and NADPH-cytochrome c reductase | Aspergillus nidulans | nitrite + NADP+ + H2O | - |
? | |
nitrate + NADPH | catalyzes the NADPH-linked reduction of ferricyanide and 2,6-dichlorophenolindophenol, chlorate- and bromate-dependent NADPH oxidation, and FMNH-linked nitrate reduction | Aspergillus nidulans | nitrite + NADP+ + H2O | - |
? |
Subunits | Comment | Organism |
---|---|---|
tetramer | 2 * 59000 + 2 * 38000, SDS-PAGE, after heat-treatment all polypeptide chains are 59 kDa | Aspergillus nidulans |
Temperature Optimum [°C] | Temperature Optimum Maximum [°C] | Comment | Organism |
---|---|---|---|
30 | - |
assay at | Aspergillus nidulans |
Temperature Stability Minimum [°C] | Temperature Stability Maximum [°C] | Comment | Organism |
---|---|---|---|
37 | - |
absence of FAD, rapid loss of activity, decreases to 50% in less than 20 min | Aspergillus nidulans |
pH Optimum Minimum | pH Optimum Maximum | Comment | Organism |
---|---|---|---|
7 | 8 | - |
Aspergillus nidulans |
7.4 | - |
assay at | Aspergillus nidulans |
Cofactor | Comment | Organism | Structure |
---|---|---|---|
cytochrome b557 | involved in intracellular electron transport from NADPH to nitrate | Aspergillus nidulans | |
FAD | contains 5.91-7.78 nmol FAD per mg of protein, activation of NADPH-nitrate reductase activity | Aspergillus nidulans | |
FAD | molybdoflavoprotein | Aspergillus nidulans | |
additional information | NADH: no effect, presence of protoheme IX | Aspergillus nidulans |