InterPro: IPR019490 Bifunctional glucose-6-phosphate/mannose-6-phosphate isomerase, C-terminal

Phosphoglucose isomerase (PGI) catalyses the interconversion of phosphoglucose and phosphofructose, and is a component of many sugar metabolic pathways. In some archaea and bacteria PGI activity occurs via a bifunctional enzyme that also exhibits phosphomannose isomerase (PMI) activity. Though not closely related to eukaryotic PGIs, the bifunctional enzyme is similar enough that the sequence includes the cluster of threonines and serines that forms the sugar phosphate-binding site in conventional PGI. This entry represents the C-terminal half of the bifunctional PGI/PMI enzyme, which contains many of the active catalytic site residues. The enzyme is thought to use the same catalytic mechanisms for both glucose ring-opening and isomerisation for the interconversion of glucose 6-phosphate to fructose 6-phosphate [1].