 GM1 consists of a sialic acid-containing oligosaccharide covalently attached to a ceramide lipid.The A1 subunit of this toxin will gain entry to intestinal epithelial cells with the assistance of the B subunit via the GM1 ganglioside receptor.Once inside, the A1 subunit will ADP ribosylate the Gs alpha subunit which will prevent its GTPase activity.