大肠埃希菌热不稳定肠毒素B亚单位在婴儿双歧杆菌中的表达

Expression of B-subunit of the Escherichia coli heat-labile enterotoxin in Bifidobacterium infantis

目的将大肠埃希菌热不稳定肠毒素B亚单位(LTB)克隆到表达载体pBV220,使LTB基因在大肠埃希菌和双歧杆菌中稳定表达。方法将LTB基因克隆到表达载体pBV220中,再分别转化大肠埃希菌DH5α和婴儿双歧杆菌,使之表达,表达产物用SDS-PAGE鉴定。并通过家兔肠袢实验验证表达蛋白的安全性。结果LTB基因在大肠埃希菌和双歧杆菌中均可稳定表达,毒性实验证明LTB保留轻微的毒性。结论稳定表达LTB的双歧杆菌为今后的口服疫苗佐剂奠定了基础。

Objective To stably express B-subunit of the Escherichia coli heat-labile enterotoxin （LTB） in E. coli and Bifidobacterium infantis. Methods LTB gene was cloned into a expression vector pBV220. This vector was designated pBV220-LTB and transformed into B. infantis and E. coli DH5α. The product was determined by SDS-PAGE. Results The ltb gene could stably express in E. coli and B. infantis. The LTB had a gentle toxicity of inducing intestinal juice secretory in rabbit by ansa intestinalis test. Conclusion This study paved the way for using Bifidobacterium-LTB recombinant as an oral vaccine adjuvant in future.