Glucose-Oxidase
- UniProt: P81156
- CAS Number: 9001-37-0
Glucose oxidase (GOD, and glucose oxidase ) is an enzyme that catalyzes the oxygen - dependent oxidation at the C1 carbon atom of the sugar is glucose.
Dimeric flavoenzyme converts glucose and oxygen to form gluconolactone and hydrogen peroxide. It comes in fungi, white-rot fungus Phanerochaete chrysosporium as the and the mold Aspergillus niger and Penicillium amagasakiense before, but has also been demonstrated for Bombyx mori. The crystal structure of the enzyme from these two fungi was determined by X-ray crystallography. The molecular mass of 120 kDa.
After binding of glucose to the enzyme of the electron transfer to the bound on the enzyme FAD, which is reduced to FADH2. The gluconolactone is released, it may spontaneously or enzymatically hydrolyzed to gluconic acid. In a second step, molecular oxygen is added to the isoalloxazine ring of FAD and the hydroperoxide system then released as hydrogen peroxide. Molecular oxygen is the natural electron acceptor, the enzyme can also work with a number of artificial acceptors.
The enzyme has great importance in the determination of glucose with glucose oxidase test. It is also frequently used as a model enzyme for electronic mini- enzyme biosensors, while the enzyme is applied to a metal surface and can pass the electrons to the redox reaction catalyzed by it.
Occurrence
Glucose oxidase is inter alia naturally in honey. It is part of the body's own secretions which already cause the bees in the transport of the flower to the hive the nectar. Exactly triggered by the glucose oxidase conversion of glucose to the germicidal or bacteriostatic hydrogen peroxide is given a great importance in the preservation of the honey in the hive.