Brain gangliosides structures

Gangliosides with short carbohydrate chains have been isolated from brain tissue of eight species of cartilaginous fish. Sequential enzymatic hydrolysis showed that the structure (16) was the major elasmobranch brain ganglioside. 

The structure of a novel L-fucose-containing ganglioside from pig cerebellum has been established (2). 9-O-Acetyl-A-acetylneuraminic acid accounts for up to 20% of the brain ganglioside fractions from man, cow, horse, pig, sheep, cat, rabbit, rat, chicken, and codfish. In the pig and cow, traces of the A-glycolyl derivative were also found. The novel trisialoganglioside, Giia (3), has been isolated and characterized and is responsible for 0.6% of the total ganglioside fraction of human brain. ... 

Another major constituent of the brain ganglioside mixture is ganglioside C3(=C3=Ggntiii)- This molecule has the basic structure of B3, but has one additional neuraminic acid residue linked by a 28-bond to the N-acetyl-neuraminic... 

Extensive studies on the chemical structure of the Tay-Sachs ganglioside have not shown a significant abnormality. As mentioned earlier, a compound with identical structure has been found among brain gangliosides of normal subjects. However, the sensitivity of these complex molecules toward treatment with alkali or acid, the possibility of spontaneous hydrolysis during handling and the complicated methods of structural identification render definite clarification of this point difficult. 

Seiter, C., 1970, The structural Analysis of Brain Gangliosides from Goldfish (Carassius Auratus) The presence of N, 8-O-diacetylneuraminic acid in the polysialoganglio-sides, Ph.D. Thesis, Ohio State University, Columbus, Ohio. 

Basic ganglioside structure without A/-acetyl neuraminic acid (sialic acid) residues. Intermediate in ganglioside biosynthesis (rat, frog, brain)... 

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