Abstract
D-Glucose dehydrogenase [β-D-glucose: NAD(P) oxidoreductase (EC 1.1.1.47)] was synthesized derepressively in a mutant of a Bacillus species which was isolated as an improved strain for D-ribose production. The enzyme was very unstable and inactivated during storage or column chromatography. The inactivation was prevented in the presence of NAD+, NADP+ or certain salts. The inactive enzyme was reactivated by the addition of NAD+, NADH, NADP+, NADPH, AMP, ADP, ATP or certain salts. The molecular weights of the inactive and active form of the enzyme were estimated to be about 45, 000 and 80, 000, respectively, by Sephadex G-150 gel filtration. Thus, it seems that the enzyme activity is regulated by monomer-dimer interconversion of the enzyme molecule.
