The enzyme phosphoinositide 5-phosphatase (EC 3.1.3.36) catalyzes the reaction
This enzyme belongs to the family of hydrolases, specifically those acting on phosphoric monoester bonds. The systematic name is phosphatidyl-myo-inositol-4,5-bisphosphate 4-phosphohydrolase. Other names in common use include type II inositol polyphosphate 5-phosphatase, triphosphoinositide phosphatase, IP3 phosphatase, PtdIns(4,5)P<sub>2</sub> phosphatase, triphosphoinositide phosphomonoesterase, diphosphoinositide phosphatase, inositol 1,4,5-triphosphate 5-phosphomonoesterase, inositol triphosphate 5-phosphomonoesterase, phosphatidylinositol-bisphosphatase, phosphatidyl-myo-inositol-4,5-bisphosphate phosphatase, phosphatidylinositol 4,5-bisphosphate phosphatase, polyphosphoinositol lipid 5-phosphatase, and phosphatidyl-inositol-bisphosphate phosphatase. This enzyme participates in inositol phosphate metabolism and phosphatidylinositol signaling system.
As of late 2007, 4 structures have been solved for this class of enzymes, with PDB accession codes , , , and .