STUDIES OF THE STRUCTURE AND FUNCTION OF PERTUSSIS TOXIN

百日咳毒素及其B低聚体与脂泡的结合 对含鞘糖脂进行了研究。百日咳毒素和B组 低聚物结合到含有神经节苷脂GD1a的脂泡上。约束： 对这些小泡的百日咳毒素在治疗后减少。 神经氨酸酶，表明唾液酸残基对 毒素与GD1a的有效结合。这些发现与 认为唾液酸残基可能在有效百日咳中发挥作用的想法 与糖脂结合的毒素。尽管这里报告的数据不是 探讨GD1a是否作为血管表面PT的功能性受体 真核细胞，这些数据提供了关于 PT能够与之结合的寡糖结构。 百日咳毒素在野生型和突变型B。 对百日咳细胞也进行了研究。百日咳毒素在两种野生型细胞中的表达 在缺乏毒素分泌的突变体中，毒素的分级是 提示百日咳毒素或其亚单位可能与 松散地与膜或与定位在膜中的蛋白质一起。

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.