Description Frequently Asked Questions Live Chat and Frequently Asked Questions are available for this Product. Analysis Note Protein determined by biuret 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 approximay 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. Quality May contain traces of amylase, maltase, glycogenase, invertase, and galactose oxidase. Unit Definition One unit will oxidize 1.0 μmole of β-D-glucose to D-gluconolactone and H2O2 per min at pH 5.1 at 35 °C, equivalent to an O2 uptake of 22.4 μl per min. If the reaction mixture is saturated with oxygen, the activity may increase by up to 100%.
Properties type Type X-S form lyophilized powder composition Protein, ~75% foreign activity Catalase ≤5 units/mg protein storage temp. −20°C