In enzymology, a galactolipid O-acyltransferase () is an enzyme that catalyzes the chemical reaction 2 mono-beta-D-galactosyldiacylglycerol acylmono-beta-D-galactosyldiacylglycerol + mono-beta-D-galactosylacylglycerol Hence, this enzyme has one substrate, mono-beta-D-galactosyldiacylglycerol, and two products, acylmono-beta-D-galactosyldiacylglycerol and mono-beta-D-galactosylacylglycerol. This enzyme belongs to the family of transferases, specifically those acyltransferases transferring groups other than aminoacyl groups. The systematic name of this enzyme class is mono-beta-D-galactosyldiacylglycerol:mono-beta-D-galactosyldiacylgly cerol acyltransferase. This enzyme is also called galactolipid:galactolipid acyltransferase. This enzyme participates in glycerolipid metabolism. References EC 2.3.1 Enzymes of unknown structure