Catalyzes the NAD(P)(+)-dependent oxidation of D-glucose to D-gluconate via gluconolactone. Is also significantly active with galactose as substrate, but not with mannose or glucose 6-phosphate. Can utilize both NAD(+) and NADP(+) as electron acceptor, with a marked preference for NADP(+). Physiologically, may be involved in the degradation of both glucose and galactose through a non-phosphorylative variant of the Entner-Doudoroff pathway. D-glucose + NAD(+) = D-glucono-1,5-lactone + H(+) + NADH D-glucose + NADP(+) = D-glucono-1,5-lactone + H(+) + NADPH D-galactose + NAD(+) = D-galactono-1,4-lactone + H(+) + NADH D-galactose + NADP(+) = D-galactono-1,5-lactone + H(+) + NADPH The KM value for NAD(+) is superior to 30 mM, it could not be defined precisely as it was impossible to reach saturation of the enzyme. Thermostable. Retains full catalytic activity after 9 hours at 55 degrees Celsius, and at 75 degrees Celsius the half-life is approximately 3 hours. Homotetramer. Belongs to the zinc-containing alcohol dehydrogenase family. Glucose 1-dehydrogenase subfamily.