Treatment with phospholipase C strongly protected monkey kidney (Vero) cells against diphtheria toxin and reduced the ability of the cells to bind125I-labelled toxin. Treatment with phospholipase D and with trypsin also protected the cells, although to a lesser extent. Phospholipase A2had no protective effect. Phospholipase C also protected fetal hamster kidney cells against the toxin. After removal of the enzymes, as well as after treatment of the cells with 4-acetamide 4′-isothiocyanostilbene 2,2′-disulfonic acid, diphtheria toxin binding capability was restored slowly, apparently by a process requiring protein synthesis, since cycloheximide blocked the restoration. The data indicate that both phospholipids and protein are involved in the binding sites for diphtheria toxin. © 1985.
Olsnes, S., Carvajal, E., Sundan, A., & Sandvig, K. (1985). Evidence that membrane phospholipids and protein are required for binding of diphtheria toxin in Vero cells. BBA - Molecular Cell Research, 846(3), 334–341. https://doi.org/10.1016/0167-4889(85)90003-5