Die enzymatische Acylierung von Lysophosphatidsäure, gesättigtem und ungesättigtem Lysolecithin

Abstract

Experiments are described on the enzymatic acylation of lysophosphatidic acid, and saturated and unsaturated lysolecithin with pairs of competing saturated, monoenoic and polyenoic fatty acids. The molar ratios of the different fatty acids which were in-corporated in high yield into the 2-position of lysophosphatidic acid, were very similar. The incorporation of the fatty acids was indepen-dent of their structure, chain length and number of double bonds. If saturated lysolecithin was the acceptor, a distinct specificity for polyenoic fatty acids was apparent: di,-tri- and tetraenoic fatty acids were preferred to the saturated and monoenoic fatty acids. On the other hand, competing fatty acids with 2 and more double bonds each were incorporated in almost equimolar ratios. The kinetics of the acylation ration with unsaturated lysolethinin as acceptor indicate a higher acylation rate. An even more pronounced specificity for unsaturated fatty acids was found. Using pairs of acyl-coenzyme A-esters, one of which was C16, the absolute and relative incorporation of this saturated fatty acid into the 2-position of saturated lysolecithin was 2 to 3 times higher than into unsaturated lysolecithin. Using pairs of acyl-CoA-esters, one of which was [DELTA] 9, 12-C18, the latter was much better incorporated into unsaturated lysolecithin than into saturated lysolecithin.