Specificity of glucose oxidase (notatin)

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Abstract
The catalytic oxidation by notatin of beta-glucose was much more rapid than that of alpha-glucose. Two samples of notatin (Y and Z), which were of equal catalytic activity in the oxidation of beta-glucose, showed very different activities in the oxidation of alpha-glucose. Sample Z oxidized alpha-glucose about 8 times faster than sample Y. Manometric study of the oxidation of alpha-flucose by these samples of notatin indicated that sample Z contained an additional component capable of catalysing mutarotation. The use of notatin for estimation of glucose formation in biological systems was discussed. The O2 uptake in presence of notatin was a reliable measure of glucose formation at any temp. if glucose was liberated in the beta-form, while at 39[degree] the mutarotation was fast enough to ensure that the O2 uptake was a true measure of the rate of appearance of either isomer. At lower temps., if glucose was liberated in the alpha-form, the concn. of notatin had to be carefully adjusted so that the oxidation of glucose did not limit the rate of the overall reaction . All 8 D-aldohexoses were tested with notatin. If the rate of oxidation of beta-glucose = 100, those of the other sugars were: mannose= 0.98, altrose = 0.16 and galactose = 0.14, while allose, gulose, isose, and talose were not oxidized. Notatin can now be considered as a specific beta-D-glucopyranose oxidase.