The ability to adhere via colonization factors to specific receptors located on the intestinal mucosa is a key virulence factor in enterotoxigenic Escherichia coli (ETEC) pathogenesis. Here, the potential glycosphingolipid receptors of the novel human ETEC colonization factor CS30 were examined by binding of CS30-expressing bacteria to glycosphingolipids on thin-layer chromatograms. We thereby found a highly specific binding of CS30-expressing bacteria to a fast-migrating acid glycosphingolipid of human and porcine small intestine, while no binding was obtained with a mutant ETEC strain unable to express CS30 fimbriae. The CS30 binding glycosphingolipid from human small intestine was isolated and characterized by mass spectrometry as sulfatide (SO3-3Galβ1Cer). Comparative binding studies using sulfatides with different ceramide compositions gave a preferential binding of CS30 to sulfatide with d18:1-h24:0 ceramide. This ceramide species of sulfatide was also isolated from human small intestine and characterized by mass spectrometry and antibody binding. These studies implicate sulfatide as candidate receptor for mediating attachment of CS30-fimbriated ETEC to human and porcine small intestinal cells. Our findings may be a basis for designing receptor saccharide analogues for inhibition of the intestinal adhesion of CS30-expressing E. coli.

中文翻译：

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产肠毒素大肠杆菌的定殖因子CS30与人和猪小肠中的硫化物结合。

通过定居因子粘附于位于肠粘膜上的特定受体的能力是肠毒素性大肠杆菌（ETEC）发病机理中的关键毒力因子。在这里，通过表达CS30的细菌与薄层色谱图上的糖鞘脂结合，检查了新型人ETEC定居因子CS30的潜在糖鞘脂受体。因此，我们发现表达CS30的细菌与人和猪小肠的快速迁移酸性糖鞘脂具有高度特异性的结合，而无法表达CS30菌毛的突变ETEC菌株则没有结合。分离了来自人小肠的与CS30结合的鞘糖脂，并通过质谱表征为硫化物（SO3-3Galβ1Cer）。使用具有不同神经酰胺组成的硫化物进行的比较结合研究显示，CS30与d18：1-h24：0神经酰胺对硫化物的优先结合。硫化物的这种神经酰胺也从人的小肠中分离出来，并通过质谱和抗体结合进行表征。这些研究表明，硫化物可作为介导CS30纤维化的ETEC附着于人和猪小肠细胞的候选受体。我们的发现可能是设计受体糖类似物以抑制表达CS30的大肠杆菌的肠粘连的基础。这些研究表明，硫化物可作为介导CS30纤维化的ETEC附着于人和猪小肠细胞的候选受体。我们的发现可能是设计受体糖类似物以抑制表达CS30的大肠杆菌的肠粘连的基础。这些研究表明，硫化物可作为介导CS30纤维化的ETEC附着于人和猪小肠细胞的候选受体。我们的发现可能是设计受体糖类似物以抑制表达CS30的大肠杆菌的肠粘连的基础。