Membrane-bound pyrroloquinoline quinone-dependent dehydrogenase in Gluconobacter oxydans M5, responsible for production of 6-(2-hydroxyethyl) amino-6-deoxy-L-sorbose

A membrane-bound protein purified from Gluconobacter oxydans M5 was confirmed to be a pyrroloquinoline quinone-dependent D-sorbitol dehydrogenase. Gene disruption and complementation experiments demonstrated that this enzyme is responsible for the oxidation of 1-(2-hydroxyethyl) amino-1-deoxy-D-sorbitol (1NSL) to 6-(2-hydroxyethyl) amino-6-deoxy-L-sorbose (6NSE), which is the precursor of an antidiabetic drug, miglitol.