[大肠杆菌H74-114株不耐热肠毒素的分离与特性]

[Isolation and characteristics of the thermolabile enterotoxin from Escherichia coli strain H74-114].

作者信息

Stepanova M V, Vertiev Iu V, Shaginian I A, Ezepchuk Iu V

出版信息

Mol Gen Mikrobiol Virusol. 1985 Dec(12):42-6.

Abstract

The modified method for isolation and purification of LT-enterotoxin from Escherichia coli strain H74-114 has been proposed. Modification is based on exclusion of concentration of bacterial cell lysates by 3-5 fold dilution and changing PH during chromatography. The proposed modification permitted to increase the yield of purified and active product 8-10 fold. The obtained preparations are homogenic due to PAAG-SDS data and immunochemical analysis. B-component of TL-enterotoxin is shown to consist of 4 subunits B in contrast to B-component of choleragen, consisting of 5 subunits. The mol mass of A component of both toxins is identical but in contrast to choleragen the component of LT-enterotoxin is not subject to proteolysis.

摘要

已提出从大肠杆菌H74 - 114菌株中分离和纯化LT - 肠毒素的改良方法。改良基于通过3 - 5倍稀释排除细菌细胞裂解物的浓缩，并在色谱过程中改变pH值。所提出的改良方法可使纯化活性产物的产量提高8 - 10倍。根据聚丙烯酰胺梯度凝胶 - 十二烷基硫酸钠（PAAG - SDS）数据和免疫化学分析，所获得的制剂具有同质性。与由5个亚基组成的霍乱毒素B组分相比，TL - 肠毒素的B组分显示由4个亚基B组成。两种毒素的A组分的摩尔质量相同，但与霍乱毒素不同，LT - 肠毒素的组分不会发生蛋白水解。