title: Glucose dehydrogenase from the thermoacidophilic archaebacterium Sulfolobus solfataricus.
abstract: Glucose dehydrogenase has been purified to homogeneity from cell extracts of the extreme thermoacidophilic archaebacterium Sulfolobus solfataricus. The enzyme utilizes both NAD+ and NADP+ as coenzyme and catalyses the oxidation of several monosaccharides to the corresponding glyconic acid. Substrate specificity and oxidation rate depend on the coenzyme present; when NAD+ is used, the enzyme binds and oxidizes specifically sugars presenting equatorial orientation of hydroxy groups at C-2, C-3 and C-4. The Mr of the native enzyme is 124,000 and decreases to about 60,000 in the presence of 6 M-guanidinium chloride and to about 30,000 in the presence of 5% (w/v) SDS. The enzyme shows maximal activity at pH 9, 77 degrees C and 20 mM-Mg2+, -Mn2+ or -Ca2+ and is fairly stable in the presence of chaotropic agents and water-miscible organic solvents such as methanol or acetone.
mesh_terms: D000596:Amino Acids / Q000032:analysis; D002236:Carbohydrate Conformation; D002237:Carbohydrate Dehydrogenases / Q000378:metabolism*; D005690:Galactose / Q000378:metabolism; D005947:Glucose / Q000378:metabolism; D042843:Glucose 1-Dehydrogenase; D005948:Glucose Dehydrogenases / Q000302:isolation & purification / Q000378:metabolism*; D007700:Kinetics; D008970:Molecular Weight; D013379:Substrate Specificity; D013822:Thermoplasma / Q000201:enzymology*; D014994:Xylose / Q000378:metabolism
chemical_list: D000596:Amino Acids; D014994:Xylose; D002237:Carbohydrate Dehydrogenases; D005948:Glucose Dehydrogenases; D042843:Glucose 1-Dehydrogenase; D005947:Glucose; D005690:Galactose