Phosphatidylinositol 3,4 bisphosphate 4 phosphatase

In enzymology, a phosphatidylinositol-3,4-bisphosphate 4-phosphatase (EC 3.1.3.66) is an enzyme that catalyzes the chemical reaction

1-phosphatidyl-myo-inositol 3,4-bisphosphate + H₂O ⇌ 1-phosphatidyl-1D-myo-inositol 3-phosphate + phosphate

Thus, the two substrates of this enzyme are 1-phosphatidyl-myo-inositol 3,4-bisphosphate and H₂O, whereas its two products are 1-phosphatidyl-1D-myo-inositol 3-phosphate and phosphate.

This enzyme belongs to the family of hydrolases, specifically those acting on phosphoric monoester bonds. The systematic name of this enzyme class is 1-phosphatidyl-1D-myo-inositol-3,4-bisphosphate 4-phosphohydrolase. Other names in common use include inositol-3,4-bisphosphate 4-phosphatase, D-myo-inositol-3,4-bisphosphate 4-phosphohydrolase, phosphoinositide 4-phosphatase, inositol polyphosphate 4-phosphatase, D-myo-inositol-3,4-bisphosphate 4-phosphohydrolase, and inositol polyphosphate 4-phosphatase type II. This enzyme participates in inositol phosphate metabolism and phosphatidylinositol signaling system.