In enzymology, a 1-acylglycerol-3-phosphate O-acyltransferase (EC 2.3.1.51) is an enzyme that catalyzes the chemical reaction acyl-CoA + 1-acyl-sn-glycerol 3-phosphate CoA + 1,2-diacyl-sn-glycerol 3-phosphate Thus, the two substrates of this enzyme are acyl-CoA and 1-acyl-sn-glycerol 3-phosphate, whereas its two products are CoA and 1,2-diacyl-sn-glycerol 3-phosphate.