Fungal pyranose oxidases: occurrence, properties and biotechnical applications in carbohydrate chemistry

Abstract

Pyranose oxidases are widespread among lignin-degrading white rot fungi and are localized in the hyphal periplasmic space. They are relatively large flavoproteins which oxidize a number of common monosaccharides on carbon-2 in the presence of oxygen to yield the corresponding 2-keto sugars and hydrogen peroxide. The preferred substrate of pyranose oxidases is D-glucose which is converted to 2-keto-D-glucose. While hydrogen peroxide is a cosubstrate in ligninolytic reactions, 2-keto-D-glucose is the key intermediate of a secondary metabolic pathway leading to the antibiotic cortalcerone. The finding that 2-keto-D-glucose can serve as an intermediate in an industrial process for the conversion of D-glucose into D-fructose has stimulated research on the use of pyranose oxidases in biotechnical applications. Unique catalytic potentials of pyranose oxidases have been discovered which make these enzymes efficient tools in carbohydrate chemistry. Converting common sugars and sugar derivatives with pyranose oxidases provides a pool of sugar-derived intermediates for the synthesis of a variety of rare sugars, fine chemicals and drugs.

Engineering of pyranose 2-oxidase for modified oxygen reactivity

“…Pyranose 2-oxidase is a well investigated oxidoreductase for industrial applications in the area of food technology and biosensors/biofuel cells [14,[52][53][54][55]. Reduced oxygen reactivity is a desirable property for some applications because of reduced The reactivity of flavoproteins with oxygen is of considerable scientific interest, and the determinants of oxygen activation and reactivity are the subject of numerous studies [39][40][41][42][43][44].…”

Kinetic Mechanism of Pyranose 2-Oxidase from Trametes multicolor

“…D-Glucose (99.5% purity), 2-d-D-glucose, and horseradish peroxidase were purchased from Sigma-Aldrich. ABTS [2,2 0 -azino-bis(3 -ethylbenzenethiazoline-6-sulfonic acid) diammonium salt] was purchased from Roche (Germany). Concentrations of the following compounds were determined using the known absorption coefficients at pH 7.0: ε 403 = 100 Â 10 3 M Spectroscopic Studies.…”

“…The enzyme was identified and isolated from several species of fungi (2) and is thought to be involved in lignin degradation by providing H 2 O 2 for lignin peroxidase (3). H 2 O 2 production by P2O can also be important for maintaining an oxidative stress level that helps control the growth of other competing organisms (4).…”

Isolation and Purification of Pyranose 2-Oxidase fromPhanerochaete chrysosporiumand Characterization of Gene Structure and Regulation

“…It also is of interest for numerous biotechnological applications, analytical methods, and synthesis of novel chemicals (16). Indications are that POX is the major glucose-oxidizing enzyme in Phanerochaete chrysosporium ligninolytic cultures, even with the fungal strain and culture conditions for which glucose 1-oxidase (GOX) (EC 1.1.3.4) was previously reported (49).…”

“…Several wood decay fungi in addition to P. chrysosporium are reported to produce POX (16), including Oudemansiella mucida, Trametes versicolor (8), Polyporus obtusus (36), Phlebiopsis gigantea (37), and Trametes multicolor (51). In general, POX oxidizes various aldopyranoses and disaccharides to the corresponding 2-keto sugars concomitant with the reduction of O 2 to H 2 O 2 (16,29).…”