Structure of gangliosides from gonads of the starfish Evasterias retifera

Abstract

Mono- and disialogangliosides were isolated from gonads of the starfish Evasterias retifera. Their structures were elucidated using chemical methods, GC-MS analysis, and enzymatic hydrolysis with neuraminidase. The monosialoganglioside has the structure 8-O-Me-Neu5Gc-α2→3-GalNAc-β1→3-Gal-β1→4-Glc-β1→1-Cer, while the disialoganglioside contains an additional Neu5Ac residue which glycosylates GalNAc in position 6. The lipid moieties of both gangliosides contain phytosphingosine (mainly C18:0) and two types of fatty acids, unsubstituted (mainly C16:0 and C18:0) and α-hydroxy acids (mainly α-hydroxy-C16:0).