Dehydroquinate synthase-like, alpha domain
Propanediol:nicotinamide adenine dinucleotide (NAD+) oxidoreductase
L-Lactaldehyde:propanediol oxidoreductase
Molecular characterization of microbial alcohol dehydrogenases.
Site-directed mutagenesis studies of the metal-binding center of the iron-dependent propanediol oxidoreductase from Escherichia coli.
Glycerol dehydrogenase. structure, specificity, and mechanism of a family III polyol dehydrogenase.
Crystal structure of an iron-dependent group III dehydrogenase that interconverts L-lactaldehyde and L-1,2-propanediol in Escherichia coli.
This enzyme belongs to the group III "iron-activated" dehydrogenases. This enzyme is homologous to glycerol dehydrogenase (D00835 in EzCatDB), whose metal cofactor is zinc ion, instead of iron (see [3]). However, this enzyme adopts iron ion as a cofactor, with slightly different binding site from that of the homologous enyzme (see [4]). According to the literature [4], although His267 does not interact with the hydroxyl group of the substrate, it might interact with it through a water molecule. Possibly, it may act as a general base-acid. Moreover, the substrate hydroxyl group is bound to the iron ion, along with Asp196, His200, His263 and His277. The iron cofactor seems to lower the pKa of the hydroxyl group, facilitating the hydride transfer from the substrate to the nicotinamide C4 atom of NAD (see [4]).