Sphingosylphosphorylethanolamine is analogous to sphingomyelin, containing an ethanolamine headgroup rather than a choline headgroup, and is thought to have similar structural functions. It has been found in some marine invertebrates, anaerobic bacteroides, some insects, and in the eukaryotic microorganism Oomycete but not in plants or mammals. It is thought that sphingosylphosphorylethanolamine may be produced when there is a lack of choline to make sphingomyelin1 and that it is probably localized in the plasma membrane, similar to sphingomyelin.2 The enzyme phosphatidylethanolamine:ceramide-phosphorylethanolamine transferase is deactivated by phospholipase C treatment but not by phospholipase A2 or phospholipase D.3
