The formation of phosphatidylinositol by acylation of 2-acyl-sn-glycero-3-phosphorylinositol in rat liver microsomes

Abstract

The conversion of 2-acyl-sn-glycero-3-phosphorylinositol into phosphatidylinositol via acyl-CoA: 2-acyl-sn-glycero-3-phosphorylinositol acyltransferase activity was found to occur in rat liver microsomes. Over a wide range of conditions, stearic acid was preferred over palmitate by the acyltransferase when these acids were presented in mixtures as acyl-CoA derivatives. The potential importance of this enzyme activity for the entry of stearic acid into the 1-position of hepatic phosphatidylinositol is further supported by its greater preference for stearate relative to the acyl-CoA:2-acyl-sn-glycero-3-phosphorylcholine acyltransferase under certain assay conditions.