In enzymology, a 1-phosphatidylinositol-3-phosphate 5-kinase (EC 2.7.1.150) is an enzyme that catalyzes the chemical reaction ATP + 1-phosphatidyl-1D-myo-inositol 3-phosphate ⇌ ADP + 1-phosphatidyl-1D-myo-inositol 3,5-bisphosphate Thus, the two substrates of this enzyme are ATP and , whereas its two products are ADP and .