The ganglioside content of the milk fat-globule membrane and the mouse mammary-tumour virus isolated from the milk of infected mice. Partial characterization of a new disialoganglioside.

The milk fat-globule membrane and the mouse mammary-tumour virus isolated from the milk of infected Swiss mice have been investigated for their content in gangliosides. When compared on the lipid phosphorus basis, viral envelope is found to contain more than twice as much lipid-bound sialic acid as fat-globule membrane. The ganglioside patterns of these two structures appear rather similar, except for the occurrence in fat-globule membrane of a low ganglioside homolog, presumably GM2, not detected in viral envelope. A common and dominant trait is the presence in both structures, as the main ganglioside, of a component which has been so far characterized as a disialoganglioside, having the same neutral glycolipid moiety as GD1a, but with both sialic acid residues displayig to Clostridium perfringens and Vibrio cholerae neuraminidase, the susceptibility typical of terminal sialic acid residues.