Tonevitskiĭ A G, Toptygin A Iu, Agapov I I, Shamshiev A T, Pfuller U, Ershova G V, Prokof'ev S A, Rakhmanova V A
University Witten/Herdecke, Berlin, Germany,
Mol Biol (Mosk). 1994 May-Jun;28(3):574-9.
A chimeric toxic protein was prepared from the mistletoe lectin I A-chain and ricin B-chain by using the disulfide exchange reaction. Ricin and chimeric protein were indistinguishable in binding to immobilized asialofetuin in ELISA. The chimeric protein was more toxic for Jurkat cells than native mistletoe lectin I, but not as effective as native ricin. In the presence of NH4Cl, which enhances the toxicity of some toxins and immunotoxins, but does not influence ricin toxicity, both ricin and chimeric toxin had equal cytotoxic activity. The possibility is discussed that the ricin B-chain protects the ricin A-chain from degradation during delivery from the cell surface to the place where it is translocated into the cytosol.
通过二硫键交换反应，利用槲寄生凝集素I A链和蓖麻毒素B链制备了一种嵌合毒性蛋白。在酶联免疫吸附测定（ELISA）中，蓖麻毒素和嵌合蛋白与固定化去唾液酸胎球蛋白的结合无法区分。嵌合蛋白对Jurkat细胞的毒性比天然槲寄生凝集素I更强，但不如天然蓖麻毒素有效。在NH4Cl存在的情况下，NH4Cl可增强某些毒素和免疫毒素的毒性，但不影响蓖麻毒素的毒性，蓖麻毒素和嵌合毒素具有同等的细胞毒性活性。文中讨论了一种可能性，即在从细胞表面递送至其转运至胞质溶胶的位置的过程中，蓖麻毒素B链可保护蓖麻毒素A链不被降解。
