Enzymology of quinoprotein glucose dehydrogenases from Acinetobacter calcoaceticus.

Ca2+-assisted, direct hydride transfer, and rate-determining tautomerization of C5-reduced PQQ to PQQH(2), in the oxidation of beta-D-glucose by soluble, quinoprotein glucose dehydrogenase.

Reconstitution of membrane-integrated quinoprotein glucose dehydrogenase apoenzyme with PQQ and the holoenzyme's mechanism of action.