Glucose oxidase
Function
Glucose oxidase catalyzes the oxidation of beta-D-glucose to D-glucono-delta-lactone and hydrogen peroxide in the presence of molecular oxygen. D-glucono-delta-lactone is sequentially hydrolyzed by lactonase to D-gluconic acid, and the resulting hydrogen peroxide is hydrolyzed by catalase to oxygen and water (PubMed:14188176, PubMed:14257628, PubMed:14299649, PubMed:15450808, PubMed:2076553, PubMed:2406261, PubMed:24283586, PubMed:28631058, PubMed:28939970, PubMed:34500289, PubMed:7826581, Ref.4, Ref.5). The activity shows high specificity to beta-D-glucose, with very low to no activity towards L-glucose, 2-deoxy-D-glucose, 3-deoxy-D-glucose, 4-deoxy-D-glucose, 5-deoxy-D-glucose, 6-deoxy-D-glucose, 3-O-methyl-D-glucose, 4-O-methyl-D-glucose, 6-O-methyl-D-glucose, 4,6-O-benzylidene-D-glucose, 5-thio-5-deoxy-D-glucose, D-mannose, D-allose, D-galactose, D-fructose, D-arabinose, D-xylose, trehalose, melibiose, L-mannomethylose, lactose, sucrose or 1,5-anhydro-D-glucitol (PubMed:14188176, PubMed:14257628, PubMed:24283586, Ref.5).
Post-translational modifications
The N-linked sugar chains of the glucose oxidase contributed to the high solubility of the enzyme in water.
Sequence Similarities
Belongs to the GMC oxidoreductase family.
Cellular localization
- Secreted
- Secreted
- Cell wall
- Cytoplasm
- Secreted
- Extracellular space
- Extracellular matrix
- The extracellular fluid contains 38% of the total activity with the remaining 62% being associated with the mycelia and distributed between the cell wall, cytoplasm and slime mucilage in the proportions of 34, 12 and 16%, respectively (PubMed:16133329). On progression from mid-exponential to stationary phase, the percentage of activity in the cytoplasm decreased 1.3-fold. Decreasing cytoplasmic activity is accompanied by 1.3-fold increases in the cell envelope and slime mucilage, with a 1.3-fold decrease in the extracellular fluid (PubMed:17787009).
Alternative names
Glucose oxidase, GOD, GOx, Beta-D-glucose:oxygen 1-oxido-reductase, gox