Waddell T, Head S, Petric M, Cohen A, Lingwood C
Department of Bacteriology, Hospital for Sick Children, Toronto, Ontario, Canada.
Biochem Biophys Res Commun. 1988 Apr 29;152(2):674-9. doi: 10.1016/s0006-291x(88)80091-3.
Two Escherichia coli cytotoxins (verotoxins 1 and 2) have been previously implicated in the cytopathology of the Hemolytic Uremic Syndrome. We have examined the glycolipid binding specificity of verotoxin (VT)2. This toxin specifically binds to globotriosyl ceramide (galactose alpha 1-4 galactose beta 1-4 glucosyl ceramide). Removal, or substitution of the terminal a galactose residue with N-acetyl galactosamine in beta 1-3 linkage, deletes binding activity. The toxin does not recognize similar terminal a galactose residues on a glycoglycerolipid. Thus the binding specificity of VT2 is the same as previously reported for VT1. Liposomes containing globotriosyl ceramide are able to specifically remove VT1 and VT2 cytotoxicity and cell lines selected in vitro for resistance to VT1 are cross resistant to VT2.
两种大肠杆菌细胞毒素（维罗毒素1和2）先前已被认为与溶血尿毒综合征的细胞病理学有关。我们检测了维罗毒素（VT）2的糖脂结合特异性。这种毒素特异性结合球三糖神经酰胺（半乳糖α1-4半乳糖β1-4葡萄糖神经酰胺）。去除末端α半乳糖残基或用β1-3连接的N-乙酰半乳糖胺取代，会消除结合活性。该毒素不识别糖甘油脂上类似的末端α半乳糖残基。因此，VT2的结合特异性与先前报道的VT1相同。含有球三糖神经酰胺的脂质体能够特异性消除VT1和VT2的细胞毒性，并且在体外选择的对VT1具有抗性的细胞系对VT2具有交叉抗性。
