Verotoxin-globotriaosyl ceramide (Gb3) binding is the linchpin in disease induced by verotoxin-producing Escherichia coli (VTEC), and defines cell sensitivity, tissue tropism, mode of systemic transport, specific cytotoxic activity and internal routing within sensitive cells. Binding explains the epidemiology of renal pathology, which may follow VTEC infection. Lipid heterogeneity of Gb3 is important in binding, and may define a growth-related signal transduction pathway used by verotoxin.