Schué V, Green G A, Girardot R, Monteil H
Institut de Bactériologie, Université Louis Pasteur, Faculté de Medicine, Strasbourg, France.
Biochem Biophys Res Commun. 1994 Aug 30;203(1):22-8. doi: 10.1006/bbrc.1994.2143.
Exposure of McCoy cultured cells to Clostridium difficile cytotoxin B or okadaic acid (OA), a potent phosphatase inhibitor, results in similar morphological changes. Using two-dimensional gel electrophoresis, we have detected a protein of approximately 77 kDa, with a pI of 4.5 (termed pp77) which is hyperphosphorylated in both cases. The level of phosphorylation of pp77 is increased by 293% and 35% after treatment with C. difficile cytotoxin B or OA, respectively. This protein was identified by microsequencing as calnexin, a protein which exhibits the characteristics of an endoplasmic reticulum (ER) chaperone.
将 McCoy 培养细胞暴露于艰难梭菌细胞毒素 B 或冈田酸（OA，一种有效的磷酸酶抑制剂）会导致相似的形态变化。利用二维凝胶电泳，我们检测到一种分子量约为 77 kDa、等电点为 4.5 的蛋白质（称为 pp77），在这两种情况下该蛋白质均发生了过度磷酸化。用艰难梭菌细胞毒素 B 或 OA 处理后，pp77 的磷酸化水平分别增加了 293%和 35%。通过微量测序鉴定该蛋白质为钙连接蛋白，它是一种具有内质网（ER）伴侣蛋白特征的蛋白质。
