pfam04295: GD_AH_second (This model is not part of the current CDD release)
D-galactarate dehydratase/Altronate hydrolase, second domain
This entry includes D-galactarate dehydratase (GarD, EC:4.2.1.42) which catalyzes the reaction D-galactarate = 5-keto-4-deoxy-D glucarate + H2O, and altronate hydrolase (altronic acid hydratase, EC:4.2.1.7), which catalyzes D-altronate = 2-keto-2- deoxygluconate + H2O. As purified, both enzymes are catalytically inactive in the absence of added Fe2+, Mn2+, and beta-mercaptoethanol. Synergistic activation of altronate hydrolase activity is seen in the presence of both iron and manganese ions, suggesting that the enzyme may have two ion binding sites. Mn2+ appears to be part of the enzyme active centre, but the function of the single bound Fe2+ ion is unknown. The hydratase has no Fe-S core. GarD structure revealed that it is a dimer in solution; each monomer has three domains, an N-terminal SAF domain (pfam08666), a second domain represented in this entry and a C-terminal domain. This domain consists of three parallel beta-strands, surrounded by three alpha-helices and it interacts with the C-terminal domain from the second chain to form a dimerization surface.
Jiyao W et al.(2023). "The conserved domain database in 2023.",