Isolation and Characterization of a Trisialyllactosylceramide, GT3, Containing an O-Acetylated Sialic Acid in Cod Fish Brain.

: An O-acetylated ganglioside that generated a trisialyllactosylceramide or GT3 by base treatment was found for the first time in cod fish brain. This ganglioside was isolated by high-performance liquid chromatography, and characterized by fast atom bombardment mass spectrometry, and proton nuclear magnetic resonance spectroscopy in addition to chemical analysis. The structure was identified as a modified GT3 in which the external sialic acid is O-acetylated at the C-9 position. The chemical structure is as follows: II3(9-O-Ac-NeuAc2-8NeuAc2-8NeuAc2-3)Lac Cer.