Description
Glucose-6-phosphate dehydrogenase (G6PD or G6PDH) (EC 1.1.1.49) is a cytosolic enzyme that catalyzes the chemical reaction:D-glucose 6-phosphate + NADP+ ↔ 6-phospho-D-glucono-1,5-lactone + NADPH + H+. This enzyme is in the pentose phosphate pathway, a metabolic pathway that supplies reducing energy to cells (such as erythrocytes) by maintaining the level of the co-enzyme nicotinamide adenine dinucleotide phosphate (NADPH).
Abbr
G6PDH, Native (Zymomonas mobilis)
Alias
G6PDH; GPD; G6PD1; G6PD
Applications
The enzyme is useful for diagnostic reagent, for example, glucose determination or CK determination, and for the specific
determination of glucose.
Enzyme Commission Number
EC 1.1.1.49
Contaminants
(as ZM-G6PDH activity = 100 %)
Glucokinase : <0.02 %
Phosphoglucomutase: <0.01 %
6-Phosphogluconate dehydrogenase : <0.02 %
Hexose-6-phosphate isomerase: <0.01 %
Glutathione reductase: <0.01 %
Molecular Weight
ca. 208000; Subunit molecular weight: ca. 52,000
Michaelis Constant
(30 mM Tris-HCI buffer, pH 8.0, at 30 °C)
Glucose 6-phosphate: 0.14 mM;
NADP+: 0.02 mM;
NAD+: 0.14 mM.
Specificity
NADP+: 70 %;
NAD+: 100 %.
Unit Definition
One unit of activity is defined as the amount of ZM-G6PDH that forms 1 μmol of NADH per minute at 30 °C.
Thermal stability
No detectable decrease in activity up to 50 °C
Storage
Stable at -20 °C for at least one year.
Synonyms
Glucose-6-phosphate dehydrogenase; G6PD; G6PDH; Glucose-6-phosphate dehydrogenase (NADP(+)); EC 1.1.1.49; Glucose-6-phosphate 1-dehydrogenase; Glucose-6-phosphate dehydrogenase; GPD
Specific Activity
more than 250 U/mg protein
Reaction
D-Glucose 6-phosphate + NAD(P) + ←→ D-Gluconolactone 6-phosphate + NAD(P)H + H+