Characterization of erythrocytic glucose-6-phosphate dehydrogenase in a mouse strain with reduced G6PD activity.
Erythrocytic glucose-6-phosphate dehydrogenase (G6PD) of a mutant mouse strain with X-linked G6PD-deficiency was purified and compared with the wildtype G6PD by biochemical and physiological characteristics. The red cell G6PD activity of the mutant was 20% of the wildtype. The Michaelis constant (Km) of the substrate glucose-6-phosphate (G6P) was higher (90 microM) for the mutant than for the wildtype (56 microM). The isoelectric focusing with a pH range from 3 to 10 showed one more enzymatically active band for the wildtype G6PD compared to the mutant enzyme. Other enzyme characteristics, however, such as Km for nicotinamide adenine dinucleotide phosphate (NADP), utilisation of 2-deoxy-glucose-6-phosphate (2dG6P) and deamino-NADP, heat stability, pH optimum, molecular weight, and glucose metabolisation via the pentosephosphate pathway were similar in mutant and wildtype enzyme.
Neifer
S
S
Landesinstitut für Tropenmedizin, Berlin, FRG.
Jung
A
A
Bienzle
U
U
D000818:Animals; D004912:Erythrocytes / Q000201:enzymology*; D019298:Glucose-6-Phosphate / Q000031:analogs & derivatives; D005954:Glucosephosphate Dehydrogenase / Q000097:blood* / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D005955:Glucosephosphate Dehydrogenase Deficiency / Q000201:enzymology* / Q000235:genetics; D005958:Glucosephosphates / Q000378:metabolism; D006863:Hydrogen-Ion Concentration; D007525:Isoelectric Focusing; D008297:Male; D051379:Mice; D008809:Mice, Inbred C3H; D008817:Mice, Mutant Strains; D008970:Molecular Weight; D009154:Mutation; D009249:NADP / Q000378:metabolism
D005958:Glucosephosphates; C015785:2-deoxyglucose-6-phosphate; D009249:NADP; D019298:Glucose-6-Phosphate; D005954:Glucosephosphate Dehydrogenase