Rolfe R D, Song W
Department of Microbiology, School of Medicine, Texas Tech University Health Sciences Center, Lubbock 79430.
Clin Infect Dis. 1993 Jun;16 Suppl 4:S219-27. doi: 10.1093/clinids/16.supplement_4.s219.
A receptor for Clostridium difficile toxin A was purified from brush border membranes (BBMs) from the small intestine of infant hamsters. The BBMs were solubilized with Triton X-114, and the solubilized receptor was purified with use of a toxin A immobilized affinity-chromatography column and differential temperature elution. SDS-PAGE and silver staining of the purified receptor revealed numerous high-molecular-weight bands. However, ligand blotting analysis with 125I-toxin A used as the probe identified a 163-kD protein as the predominate toxin A-binding molecule. Toxin A bound to the purified receptor at physiological temperature, but the amount of toxin bound increased at lower temperatures. Bovine thyroglobulin bound to toxin A and inhibited its binding to the purified receptor. Preincubation of the receptor with lectins produced by Bandeirea simplicifolia or Datura stramonium reduced specific binding by 125I-toxin A. Our data indicate that the purified toxin A receptor from small intestine BBMs of infant hamsters is a galactose- and N-acetylglucosamine-containing glycoprotein.
从幼年仓鼠小肠的刷状缘膜（BBMs）中纯化出艰难梭菌毒素A的受体。用Triton X - 114溶解BBMs，利用固定化毒素A的亲和层析柱和差示温度洗脱法纯化溶解的受体。纯化受体的SDS - PAGE和银染显示出许多高分子量条带。然而，以125I - 毒素A作为探针的配体印迹分析确定一种163 - kD的蛋白质是主要的毒素A结合分子。毒素A在生理温度下与纯化的受体结合，但在较低温度下结合的毒素量增加。牛甲状腺球蛋白与毒素A结合并抑制其与纯化受体的结合。用单叶豆或曼陀罗产生的凝集素对受体进行预孵育可降低125I - 毒素A的特异性结合。我们的数据表明，从幼年仓鼠小肠BBMs中纯化的毒素A受体是一种含半乳糖和N - 乙酰葡糖胺的糖蛋白。
