Reaction catalyzed by 1-phosphatidylinositol-5-phosphate 4-kinase (2.7.1.149)
ATP
+
=
ADP
+
ATP
+
1-phosphatidyl-1D-myo-inositol 5-phosphate
=
ADP
+
1-phosphatidyl-1D-myo-inositol 4,5-bisphosphate