The formation of phosphatidylglycerol and other phospholipids by the transferase activity of phospholipase D

Abstract

1. Purified phospholipase D can catalyse the transfer of a ;phosphatidyl' unit from lecithin to various aliphatic alcohols such as glycerol, ethanolamine, methanol and ethylene glycol with the formation of the equivalent phospholipid. 2. The transferase reaction occurs simultaneously with hydrolase activity but at high alcohol concentrations the former predominates. 3. The acceptor molecule must contain a primary alcoholic grouping. 4. The chromatographic and ionophoretic mobilities of the deacylation products of many enzymically synthesized phospholipids are reported. 5. Enzymically prepared phosphatidylglycerol has been isolated in good yield. Chemical degradation showed that the ;phosphatidyl unit' of lecithin had been transferred predominantly to the alpha-hydroxyl groups of glycerol. 6. Water-soluble alcohols can markedly stimulate the liberation of choline from ultrasonically treated lecithin by phospholipase D. The stimulation is usually due to an increase in hydrolase activity although often the associated transferase activity contributes.