Isolation and preliminary characterization of novel polysialogangliosides from embryonic chick brain.

Preparative thin-layer chromatography was used to isolate from embryonic chick brains four different polysialogangliosides which moved below GT1b on TLC plates. These possessed molar sialic acid-to-sphingosine ratios of 4:1, 5:1, 6:1, and 7:1, respectively. Mild neuraminidase (Clostridium perfringens) treatment of the three most highly sialylated fractions gave GT1b and GD1b transiently, but the only accumulating ganglioside was GM1. All three polysialogangliosides were also found in Elasmobranch brains. During development of he chicken the concentrations of the two most slow-moving fractions ("hexa"-, and "septa" -sialogangliosides) decreased.