Conversion of radiolabelled ethanolamine plasmalogen into the dimethylethanolamine and choline analogue via transphosphatidylation by phospholipase D from cabbage.

Starting from biosynthetically prepared ethanolamine plasmalogen 14C-labelled in the O-alkenyl moiety, choline and dimethylethanolamine plasmalogen were prepared by transphosphatidylation utilizing phospholipase D from cabbage. Investigation of the time course of the reaction showed that transphosphatidylation was simultaneously accompanied by hydrolysis of both the substrate and the desired product, resulting in a maximum of product yield after 1-3 h under the reaction conditions investigated. Optimal reaction conditions gave yields of 40% and 62% (of total radioactivity) respectively for the purified choline and dimethylethanolamine derivatives.