Schué V, Green G A, Girardot R, Monteil H
Laboratoire de Toxinologie Bactérienne, Faculté de Médecine, Université Louis-Pasteur, Strasbourg, France.
Toxicon. 1994 Dec;32(12):1581-92. doi: 10.1016/0041-0101(94)90317-4.
The cytotoxins from Clostridium difficile (toxin B) and Clostridium sordellii (toxin L) induce rounding of cultured cells. The cellular effects induced by these two cytotoxins are clearly distinct, suggesting that both toxins use a similar, but not identical mechanism for cell intoxication. We have employed the technique of two-dimensional PAGE for the separation of 32P-labelled cell lysates of McCoy cultured cells to investigate changes in the phosphorylation status of cellular proteins after treatment with toxin B and with toxin L. The two-dimensional electrophoresis patterns suggest the implication of an 80,000 mol. wt cellular protein (named pp80c) in the cytopathic action of the cytotoxin from C. sordellii. This protein shows immunoreactivity with non-muscle caldesmon. Toxin B, however, does not affect the phosphorylation of pp80c, but alters the phosphorylation of another cellular protein, pp77, indicating another mechanism for cell intoxication. In addition, our experiments suggest that the mechanism of action of okadaic acid, a phosphatase inhibitor which causes cell rounding similar to that induced by C. sordellii, and these two cytotoxins are different.
艰难梭菌的细胞毒素（毒素B）和索氏梭菌的细胞毒素（毒素L）可诱导培养细胞变圆。这两种细胞毒素所诱导的细胞效应明显不同，这表明两种毒素利用相似但不完全相同的机制使细胞中毒。我们采用二维聚丙烯酰胺凝胶电泳技术分离经32P标记的 McCoy 培养细胞的细胞裂解物，以研究用毒素B和毒素L处理后细胞蛋白质磷酸化状态的变化。二维电泳图谱表明，一种分子量为80,000的细胞蛋白（命名为pp80c）参与了索氏梭菌细胞毒素的细胞病变作用。该蛋白与非肌肉钙调蛋白有免疫反应性。然而，毒素B并不影响pp80c的磷酸化，但会改变另一种细胞蛋白pp77的磷酸化，这表明存在另一种细胞中毒机制。此外，我们的实验表明，冈田酸（一种磷酸酶抑制剂，可导致细胞变圆，类似于索氏梭菌所诱导的细胞变圆）与这两种细胞毒素的作用机制不同。
