Structural analysis of a unique hybrid-type ganglioside with isoglobo-, neolacto-, and ganglio-core from the gills of the Pacific salmon (Oncorhynchus keta)

Monosialosyl gangliosides from the gills of the Pacific salmon, Oncorhynchus keta, have been prepared by solvent extraction and DEAE-Sephadex column chromatography. The unknown acidic glycolipids (M14 and M15) with slower mobility than GM1a on thin-layer chromatography were separated by Iatrobeads column chromatography and were characterized by compositional analysis, methylation analysis, chemical, and enzymatic degradation, negative-ion LSIMS, and 1H nuclear magnetic resonance spectroscopy. Both M14 and M15 contained a same oligosaccharide core with isoglobo-, neolacto-, and ganglio-series as follows:The only difference between M14 and M15 was in fatty acid acylation. Analysis of the fatty acids indicated a predominance of C24:1 fatty acid in M14 and shorter chain saturated fatty acids, C14:0 and C16:0, in M15.