Membrane-Bound SN-2-Monoacylglycerol Acyltransferase (MGAT) is Involved in Triacylglycerol Synthesis

Abstract

Sunflower microsomal preparations catalysed the incorporation of radioactivity from [¹⁴C]oleoyl-CoA in the presence of sn-2-monoacylglycerol (2-MAG) Similar results were obtained using sn-2-mono-[¹⁴C]oleoylglycerol and non-radioactive acyl-CoA. The observations were consistent with the activity of a monoacylglycerol acyltransferase (MGAT, E.C. 2.3.1.22.) catalysing the acylation of MAG yielding diacylglycerol (DAG), and the rapid utilization of DAG in TAG synthesis. The MGAT was particularly efficient with the 2-MAG substrate and was selective for monounsaturated acyl species. Similar membrane-bound MGAT was also present in linseed (Linum usitatissimum L.), Mortiella alpina, Candida curvata D. and Saccharomyces cerevisiae.