Activating Compound | Comment | Organism | Structure |
---|---|---|---|
spermidine | activation constant: 0.2 mM | Escherichia coli |
Inhibitors | Comment | Organism | Structure |
---|---|---|---|
NADH | allosteric inhibition, inhibition is not reversed by NAD+, AMP, or spermidine | Escherichia coli | |
NADPH | when NADP+ is the varied substrate, NADPH NADPH is a competitive inhibitor both in the presence and absence of Mg2+, linear competitive inhibition. When glucose 6-phosphate is the varied substrate NADPH causes linear noncompetitive inhibition | Escherichia coli |
KM Value [mM] | KM Value Maximum [mM] | Substrate | Comment | Organism | Structure |
---|---|---|---|---|---|
additional information | - |
additional information | the initial velocity plots of the enzyme follow the Michaelis-Menten equation in the absence of NADH. In its presence, however, the velocity versus substrate plots for NADP+ become sigmoidal but remain hyperbolic for glucose 6-phosphate as the variable substrate. Inhibition against both of the substrates of the enzyme by NADH is noncompetitive. The inhibition curves for NADH are also sigmoidal, suggesting a multisite binding of the inhibitor on the enzyme surface | Escherichia coli | |
0.015 | - |
NADP+ | pH 8.0, temperature not specified in the publication | Escherichia coli | |
0.07 | - |
D-glucose 6-phosphate | pH 8.0, temperature not specified in the publication | Escherichia coli |
Metals/Ions | Comment | Organism | Structure |
---|---|---|---|
Mg2+ | activates, no absolute requirement. In the presence of saturating concentrations of spermidine or other polycations, Mg2+ ions have no further stimulatory effect | Escherichia coli |
Natural Substrates | Organism | Comment (Nat. Sub.) | Natural Products | Comment (Nat. Pro.) | Rev. | Reac. |
---|---|---|---|---|---|---|
D-glucose 6-phosphate + NADP+ | Escherichia coli | oxidative pentose pathway | 6-phospho-D-glucono-1,5-lactone + NADPH + H+ | - |
? | |
D-glucose 6-phosphate + NADP+ | Escherichia coli B / ATCC 11303 | oxidative pentose pathway | 6-phospho-D-glucono-1,5-lactone + NADPH + H+ | - |
? |
Organism | UniProt | Comment | Textmining |
---|---|---|---|
Escherichia coli | - |
- |
- |
Escherichia coli B / ATCC 11303 | - |
- |
- |
Purification (Comment) | Organism |
---|---|
- |
Escherichia coli |
Specific Activity Minimum [µmol/min/mg] | Specific Activity Maximum [µmol/min/mg] | Comment | Organism |
---|---|---|---|
5.7 | - |
pH 8.0, temperature not specified in the publication | Escherichia coli |
Storage Stability | Organism |
---|---|
-20°C, 0.05 M Tris-Cl buffer containing 1 mM glucose 6-phosphate, pH 7.5, stable for over 2 months | Escherichia coli |
Substrates | Comment Substrates | Organism | Products | Comment (Products) | Rev. | Reac. |
---|---|---|---|---|---|---|
D-glucose 6-phosphate + NADP+ | - |
Escherichia coli | 6-phospho-D-glucono-1,5-lactone + NADPH + H+ | - |
? | |
D-glucose 6-phosphate + NADP+ | oxidative pentose pathway | Escherichia coli | 6-phospho-D-glucono-1,5-lactone + NADPH + H+ | - |
? | |
D-glucose 6-phosphate + NADP+ | - |
Escherichia coli B / ATCC 11303 | 6-phospho-D-glucono-1,5-lactone + NADPH + H+ | - |
? | |
D-glucose 6-phosphate + NADP+ | oxidative pentose pathway | Escherichia coli B / ATCC 11303 | 6-phospho-D-glucono-1,5-lactone + NADPH + H+ | - |
? |
pH Optimum Minimum | pH Optimum Maximum | Comment | Organism |
---|---|---|---|
8 | - |
assay at | Escherichia coli |
Cofactor | Comment | Organism | Structure |
---|---|---|---|
NADP+ | almost specific for NADP+ as coenzyme. In presence of 2 and 3 mM NAD+ the velocity is about 2% compared to NADP+ | Escherichia coli |
Ki Value [mM] | Ki Value maximum [mM] | Inhibitor | Comment | Organism | Structure |
---|---|---|---|---|---|
0.01 | - |
NADPH | pH 8.0, temperature not specified in the publication, varied substrate: NADP+ | Escherichia coli | |
0.04 | - |
NADPH | pH 8.0, temperature not specified in the publication, varied substrate: glucose 6-phosphate, slope inhibition constant | Escherichia coli | |
0.18 | - |
NADPH | pH 8.0, temperature not specified in the publication, varied substrate: glucose 6-phosphate, intercept inhibition constant | Escherichia coli |