STUDIES OF THE STRUCTURE AND FUNCTION OF PERTUSSIS TOXIN

百日咳毒素及其B寡聚体与脂质囊泡的结合 含有鞘糖脂的化合物。 百日咳毒素和 B寡聚体结合到含有神经节苷脂GD1a的脂质囊泡上。 结合 百日咳毒素对这些囊泡的作用在治疗后减少， 囊泡与神经氨酸酶，这表明唾液酸残基是 这对于毒素与GD1a的有效结合很重要。 这些发现 这与唾液酸残基可能在 百日咳毒素与糖脂的有效结合。 虽然数据 本文报道的没有涉及GD1a是否作为功能性受体 对于真核细胞表面的PT，这些数据提供了信息， 关于PT能够 约束力野生型和突变型百日咳毒素的定位 B。还研究了百日咳细胞。 百日咳毒素在两种野生型 细胞和突变体缺乏分泌的毒素分级 该膜表明百日咳毒素或其亚单位可能 与细胞膜或位于细胞膜上的蛋白质松散地结合 膜的

The binding of pertussis toxin and it B oligomer to lipid vesicles containing glycosphingolipids was studied. Both pertussis toxin and the B oligomer bound to lipid vesicles containing ganglioside GD1a. Binding of pertussis toxin to these vesicles decreased upon treatment of the vesicles with neuraminidase, suggesting that sialic acid residues are important for efficient binding of the toxin to GD1a. These findings are consistent with the idea that sialic acid residues may play a role in efficient pertussis toxin binding to glycolipids. Although the data reported here do not address whether GD1a acts as a functional receptor for PT on the surface of eukaryotic cells, these data provide information concerning the oligosaccharide structures to which PT is capable of binding. The localization of pertussis toxin within wild-type and mutant B. pertussis cells was also studied. Pertussis toxin in both wild-type cells and in mutants deficient in the secretion of the toxin fractionated with the membrane suggesting that pertussis toxin or its subunits may associate loosely with membranes or with proteins localized in the membrane.