Pyranose 2-oxidase

This enzyme oxidizes a- and P-anomers of D-glucose to the same extent and shows excellent stability and sensitivity about twice that for the methods with immobilized glucose oxidase. In this approach, pyranose oxidase is immobilized on tresylate-poly(vinylalcohol) beads and packed into a stainless column and peroxidase is immobilized on tresylate-hydrophylic vinyl polymer beads and packed into a transparent FITE tube that is used as the CL flow cell. The H202... 

Fig. 8.5 The pyranose oxidase-catalyzed oxidation of y -D-glucose leads to the formation of glucosone. Educt and product differ by 2 Da.

Wood-degrading fungi produce a family of pyranose oxidases (EC 1.1.3.10), enzymes catalyzing the oxidation at C-2 of several aldoses. A simple and convenient conversion of D-glucose into D-arabino-hexos-2-ulose involves the use of a pyranose-2-oxidase isolated from Polyporus obtusus, which was purified and immobilized on activated CH-Sepharose 4B.446... 

H. J. Danneel, E. Rossner, A. Zeeck, and F. Giffhorn, Purification and characterization of a pyranose oxidase from the basidiomycete Peniophora gigantea and chemical analyses of its reaction products, Eur. J. Biochem., 214 (1993) 795-802. 

A similar approach was used for the detection of monosaccharides [56] pyranose oxidase delivered a suitable oxidase-based sensor with the hydrogen peroxide being determined again via the direct electron transfer from the carbon paste electrode to the enzyme horseradish peroxidase. In aU bi-enz5mie systems, both the enzymes were entrapped within the carbon paste. These electrodes were used as detectors in a liquid chromatography system allowing the simultaneous determination not only of several carbohydrates but also of ethanol within approximately 20 min. Ethanol production and carbohydrate consumption were monitored on-line during a fermentation of P. stipitis for 16 h (see also Section 11.2.3). 

Figure 16.2-27. Oxidation of carbohydrates specifically at C-2 by pyranose oxidase (P20).

Table 16.2-6. Substrates and oxidation products of pyranose oxidase.

Figure 16.2-28. Isomerization of D-glucose to D-fructose with pyranose oxidase (P20) and coupling of hydrogen peroxide to a synthetic reaction (Cetus process).

Pyranose oxidase Enzyme screening using MALDI-ToF 87... 

S. (2008) Pyranose oxidase biosensor based on carbon nanotube-modified carbon paste electrode. Sens. Actuators, B, 132, 159-165. 

The immobilization of pyranose oxidase and horseradish peroxidase in activated resins associated with a spectrophotometric reaction based on the formation of Bindshedler s green (k = ITl nm) permits the determination of sorbitol in a FIA format with a detection limit of 1.2 pmol L [62]. Prior to enzyme conversion, samples suffer an online treatment based on passage through a cleanup column filled with a strongly basic anion exchange resin, positioned after the injection valve. This step was of the utmost importance during the analysis of serum samples and can also be exploited for the analysis of foods and... 

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