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过氧化氢酶Glucose Oxidase:Catalase Ratio 100:1
水溶解试验Solubility in Water 合格
活性Specific Activity,25°C >100
Synonym β-D-Glucose:oxygen 1-oxidoreductase
G.Od.
GOx
General description Molecular Weight: 160 kDa (gel filtration)
pI: 4.2
Extinction coefficient: E1% = 16.7 (280 nm)
Glucose oxidase from Aspergillus niger is a dimer consisting of 2 equal subunits with
a molecular weight of 80 kDa each. Each subunit contains one flavin adenine dinulceotide
moiety and one iron. The enzyme is a glycoprotein containing approximately 16% neutral
sugar and 2% amino sugars. The enzyme also contains 3 cysteine residues and 8 potential
sites for N-linked glycosylation.
Glucose oxidase is capable of oxidizing D-aldohexoses, monodeoxy-D-glucoses, and methyl-D-glucoses at varying rates.
The pH optimum for glucose oxidase is 5.5, while it has a broad activity range of pH
4-7. Glucose oxidase is specific for β-D-glucose with a KM of 33-110 mM.
Glucose oxidase does not require any activators, but it is inhibited by Ag+, Hg2+, Cu2+,
phenylmercuric acetate, and p-chloromercuribenzoate. It is not inhibited by the
nonmetallic SH reagents: N-ethylmaleimide, iodoacetate, and iodoacetamide.
Glucose oxidase can be utilized in the enzymatic determination of D-glucose in solution.
As glucose oxidase oxidizes β-D-glucose to D-gluconolactate and hydrogen
peroxide, horseradish peroxidase is often used as the coupling enzyme for glucose
determination. Although glucose oxidase is specific for β-D-glucose, solutions of
D-glucose can be quantified as α-D-glucose will mutorotate to β-D-glucose as the
β-D-glucose is consumed by the enzymatic reaction.