Isolation and characterization of Shigella shigae cytotoxin.
Isolation and characterization of Shigella shigae cytotoxin.
复制标题
志贺志贺氏菌细胞毒素的分离和表征。
DOI：
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发表时间：
1980
影响因子：
4.8
通讯作者：
K. Eiklid
中科院分区：
文献类型：
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作者：
S. Olsnes;K. Eiklid
志贺菌细胞毒素分离压力透析培养基和26岁的部分纯化的毒素样品。毒素吸附到柱的酸处理甲壳素在低盐浓度和洗脱用1 M NaCl。用125 I标记部分纯化的毒素，并在酸处理的甲壳素上进行层析。将用1 M NaCl洗脱的标记物质与作为载体的未标记兔血红蛋白混合，并通过DE 52柱上的层析和通过蔗糖梯度离心进一步纯化毒素。在十二烷基硫酸钠存在下的聚丙烯酰胺凝胶电泳中，纯志贺氏菌毒素迁移为两条带，对应于分子量为30，500和约11，000。完整的毒素可以由一条重链和四到五个轻链拷贝组成。在等电聚焦实验中，志贺氏菌毒素从pH 5.8和pH 7.5之间的宽区域中回收。这似乎是由于在大和小链的电荷异质性。测试的大多数细胞系甚至对高浓度的志贺氏菌毒素具有完全抗性。Vero细胞和一株HeLa细胞对该毒素非常敏感，2.5 μ g/ml纯毒素可使HeLa细胞蛋白质合成抑制50%。
Shigella shigae cytotoxin was isolated from pressure-dialyzed culture medium and from a 26-year-old sample of partially purified toxin. The toxin was adsorbed to a column of acid-treated chitin at low salt concentration and eluted with 1 M NaCl. The partially purified toxin was labeled with 125 I and resubmitted to chromatography on acid-treated chitin. The labeled material eluted with 1 M NaCl was mixed with unlabeled rabbit hemoglobin as a carrier and the toxin was further purified by chromatography on a DE52 column and by sucrose gradient centrifugation. In polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate, the pure Shigella toxin migrated as two bands corresponding to molecular weights of 30,500 and of about 11,000. The intact toxin may consist of one heavy chain and four to five copies of the light chain. In isoelectric focusing experiments, Shigella toxin was recovered from a broad zone between pH 5.8 and pH 7.5. This appears to be due to charge heterogeneities both in the large and the small chain. Most cell lines tested were completely resistant even to high concentrations of Shigella toxin. Vero cells and one strain of HeLa cells were very sensitive, 2.5 pg/ml of pure toxin induced 50% inhibition of protein synthesis overnight in HeLa cells.