Quinoprotein glucose dehydrogenase from Acinetobacter calcoaceticus

Bacterial conversion of glucose into gluconic acid frequently proceeds via a quinoprotein glucose dehydrogenase (EC 1.1.99.17), an enzyme using pyrrolo-quinone (PQQ) as the coenzyme. Besides glucose the enzyme oxidizes other aldoses. As the properties of this enzyme, its localization and mode of coupling to the respiratory chain are largely unknown, it was decided to isolate the glucose dehydrogenase from Acinetobacter calcoaceticus . The enzyme was purified by CM-sepharose, hydroxy-apatite, and finally a gel filtration chromatography step. Its physicochemical properties are characterized.