Abstract:

As one of the main factors causing bacterial food poisoning and gastroenteritis， Staphylococcal enterotoxins （SEs） is a group of soluble small-molecule proteins with similar structural toxicity and different serotypes with the average molecular mass of 26~30 kD. To prepare pure products of SEs， the gene sequence of SEA， SEB， SEC， SED and SEE were synthesized， then the proraryotic expression vectors of five enterotoxins were constructed and transferred into BL21（DE3） cells for expression. SDS-PAGE and Western blot showed that the five enterotoxin proteins were successfully expressed， and a amount of soluble proteins could be obtained at a lower induction temperature （16 ℃）. In this study， five soluble proteins of Staphylococcal enterotoxin were successfully prepared， which laid a foundation for better solving the food safety problems caused by SEs in the future.

Key words: Staphylococcal enterotoxins, food poisoning, prokaryotic expression vectors, soluble proteins

摘要：

金黄色葡萄球菌肠毒素（Staphylococcal enterotoxins，SEs）是一组结构毒力相似、血清型不同的可溶性小分子蛋白质，平均分子质量为26~30 kD，是引起细菌性食物中毒及肠胃炎的主要因素之一。为了制备金黄色葡萄球菌肠毒素的纯品，首先合成了SEA、SEB、SEC、SED和SEE的基因序列，然后构建了5种肠毒素的原核表达载体，分别转入BL21（DE3）细胞中进行诱导表达。通过SDS-PAGE和Western blot验证，5种肠毒素蛋白均被成功表达，并且在较低的诱导温度（16 ℃）获得一定量的可溶性蛋白。成功制备了5种金黄色葡萄球菌肠毒素的可溶性蛋白，为今后更好地解决因SEs引起的食品安全问题奠定了基础。

关键词: 金黄色葡萄球菌肠毒素, 食物中毒, 原核表达载体, 可溶性蛋白