EFFECTS OF DEFINED SYNTHETIC PHOSPHOLIPIDS ON GLYCOSYLATION PROCESSES - MODIFICATIONS OF MEMBRANE-BOUND N-ACETYLGLUCOSAMINYL-TRANSFERASE AND SOLUBILIZED SIALYL-TRANSFERASE ACTIVITIES

The effects of phosphatidylcholine synthetic derivatives are studied in 2 different [mouse liver] glycosyltransferasic systems, a membranous mitochondrial N-acetyglucosaminyl-transferase and a solubilized microsomal sialyl-transferase. There was a strong inhibitory effect of lysophosphatidylcholines in these glycosylation processes. The relationship between this inhibitory effect and the chemical structure of the studied phospholipids was investigated. The most important inhibitory effect is obtained with a molecule containing a long aliphatic side chain in sn-1 of glycerol, a carbon atom devoid of any large group in sn-2 and an hydrophilic part in sn-3 (especially choline).