1-Deoxy-1-phosphatidylethanolamino-lactitol-type neoglycolipids serve as acceptors for sialyltransferases from rat liver golgi vesicles.

1-Deoxy-1-phosphatidylethanolamino-lactitols (LacPtdEtns), 1-deoxy-1-phosphatidylethanolamino-sialyllactitols (NeuAcLacPtdEtns) and their corresponding N-acetylated derivatives were synthesized and characterized by fast-atom-bombardment mass spectrometry (FAB MS). The neoglycolipids were used as acceptors for sialyltransferases from rat liver Golgi vesicles. Sialylation rates were as good as or even better than those obtained with the corresponding authentic acceptors lactosylceramide (LacCer) and ganglioside GM3. The sialylation of LacPtdEtns and NeuAcLacPtdEtns yielded sialyl and disialyl compounds, respectively, as shown by FAB MS analysis of the reaction products. The results of competition experiments indicate that the neoglycolipids and the authentic acceptors are sialylated by the same sialyltransferases.