Glucose-06-phosphatase inactivation and peroxidation of phosphatidylcholine in microsomal membranes

Abstract

Peroxidation induced by ascorbate on phospholipids of isolated rat liver microsomes were accompanied by losses in glucose-06-phosphatase activity (EC 3.1.3.9.). The existence of marked differences in the degradation rate for each phospholipid suggests a relationship between the alteration of phosphatidylcholine containing one saturated and one unsaturated fatty acid and the decrease in activity of glucose-06-phosphatase; the inactivation of this enzyme was unrelated to the alteration of other phospholipids. These results support the idea that glucose-06-phosphatase and molecules of phosphatidylcholine having one saturated and one unsaturated fatty acid are in close apposition within the microsomal membrane.