| Type: | Family | Name: | Fructose-1,6-bisphosphatase, class V |
| Description: | Fructose-1,6-bisphophatase (FBPase) catalyses the hydrolysis of D-fructose-1,6-bisphosphate (FBP) to D-fructose-6-phopshate (F6P) and orthophosphate, and is a key enzyme in gluconeogenesis []. Three different groups of FBPases have been identified in eukaryotes and bacteria (FBPase I-III) []. None of these groups have been found in archaea so far, though a new group of FBPases (FBPase IV) which also show inositol monophosphatase activity has recently been identified in archaea [].Proteins in this entry are though to represent a new group of FBPases (FBPase V) which are found in thermophilic archaea and a hyperthermophilic bacterium Aquifex aeolicus[]. The characterised members of this group show strict substrate specificity for FBP and are suggested to be the true FBPase in these organisms [, ]. A structural study suggests that FBPase V has a novel fold for a sugar phosphatase, forming a four-layer alpha-beta-beta-alpha sandwich, unlike the more usual five-layered alpha-beta-alpha-beta-alpha arrangement []. The arrangement of the catalytic side chains and metal ligands was found to be consistent with the three-metal ion assisted catalysis mechanism proposed for other FBPases. | Short Name: | FBPase_V |
