 Finally, the substrate binding site consists of the residues Asp123, His256, His274 as well as a water molecule.Encoded by the gene gldA, the enzyme glycerol dehydrogenase, GlyDH catalyzes the oxidation of glycerol to glycerone.Unlike more common pathways utilizing glycerol, GlyDH effectively oxidizes glycerol in anaerobic metabolic pathways under ATP-independent conditions (a useful mechanism in the breakdown of glycerol in bacteria).