Isolation and partial characterization of human kidney gangliosides

1. Eight gangliosides were purified from chloroform/methanol extracts of human kidneys by using modified Folch partition, dialysis, ethanol precipitation, silicic acid column chromatography and preparative thin-layer chromatography. 2. By thin-layer chromatographic behaviour and gas-liquid chromatographic determinations the main gangliosides in human kidney are N-acetylneuraminyllactosylceramide (74% of total) and di-N-acetylneuraminyllactosylceramide (19% of total). 3. Five hexosamine-containing fractions were isolated. Four of them were homogeneous on thin-layer chromatography, and one contained two gangliosides. By gas-liquid chromatography-mass spectrometry it was shown that two gangliosides (together 5% of total) contain glucosamine, and one (1% of total) contains galactosamine. The other of the glucosamine gangliosides contains fucose in addition to the usual sugars found in gangliosides. Of the two remaining hexosamine positive fractions (together 1% of total) one was homogeneous on thin-layer chromatography, the other contained two gangliosides. These two fractions contained both glucosamine and galactosamine. 4. The main long-chain base in all fractions was sphingosine.