Characterization of Two Novel Pyruvylated Glycosphingolipids Containing 2'-Aminoethylphosphoryl(—»6)-Galactose from the Nervous

Two novel acidic glycosphingolipids containing pyruvylated galactose were purified from the nervous tissue of Aplysia kurodai by successive Iatrobeads column chromatographies. By component analysis, sugar analysis, permethylation studies, fast atom bombardment-mass spectrometry, and proton magnetic resonance spectrometry, the structures of these acidic glycosphingolipids, named F-9 and FGL-I, were determined to be: [3,4-O-(S-l-carboxyethylidene)]Gal£l—3GalNAcal->3[6'-O-(2-aminoethylphosphonyl)Galal->2](2-aminoethylphosphoryl->6)Gal;91-+4Glc#l->lceramide and [3,4-0-(S-l-carboxyethyl-idene)]Gal£l->3GalNAcal—3(Fucd—2)(2-aminoethylphosphoryl—6)Gal£l->4Glc£l-lceramide, respectively. Their major aliphatic components are palmitic acid, octadeca-4-sphingenine and anteisononadeca-4-sphingenine. Thus, pyruvylated glycosphingolipids containing phosphoethanolamine in addition to or in place of 2-aminoethylphosphonate are present in the nervous system of Aplysia. In our systematic studies on the structures of glycolipids in the tissues of Aplysia, sialic acid-containing glycosphin-golipids, gangliosides, have never been found. Instead