To be defined as a ganglioside, a lipid substance isolated from nervous tissue must contain in its structure

Gangliosides They are formed when ceramide oligo-saccharides have at least one molecule of NANA (N-acetyl neuraminic acid) (sialic acid) attached to them. Ceramide--Glucose--galactose--NANA; this is designated as GM3 (ganglioside M3). Gangliosides contribute to the stability of paranodal junctions and ion channel clusters in myelinated nerve fibers. Autoantibodies to GM1 disrupt lipid rafts, paranodal or nodal structures, and ion channel clusters in peripheral motor nerves.Ref: DM Vasudevan - Textbook of Biochemistry, 8th edition, page no: 82