Identification and expression of the genes encoding a reactivating factor for adenosylcobalamin-dependent glycerol dehydratase

Adenosylcobalamin-dependent glycerol dehydratase undergoes inactivation by glycerol, the physiological substrate, during catalysis, In permeabilized c ells of Klebsiella pneumoniae, the inactivated enzyme is reactivated in the presence of ATP, Mg2+, and adenosylcobalamin. We identified the two open r eading frames as the genes for a reactivating factor for glycerol dehydrata se and designated them gdrA and gdrB. The reactivation of the inactivated g lycerol dehydratase by the gene products was confirmed in permeabilized rec ombinant Escherichia coli cells coexpressing GdrA and GdrB proteins with gl ycerol dehydratase.