志贺毒素A/B(ShT-A/B)亚单位基因的克隆与序列分析

Cloning and Sequence Analysis of Shiga Toxin A, B Gene Subunits from Shigella dysenteriae Type I

应用PCR技术从Ⅰ型痢疾志贺茵(Shigella dysenteriae type Ⅰ)中,分别扩增出约895bp和225bp的成熟ShT-A,B基因片段,直接克隆至pGEM-T载体中,经蓝白斑筛选、PCR和双酶切鉴定正确后,命名为pGEM-ShTA_2和pGEM-ShTB_3。测序结果表明,插入的片段是ShT-A,ShT-B,且与GenBank中ShT-A,B核酸序列完全一致,从而为重组ShT-A,B的表达研究奠定了基础。

A 895-bp fragment and a 225-bp fragment of the genes encoding the mature ShT-A and ShT-B subunit from the Shigella dysenteriae type I were amplified by using PCR technology, respectively. The ShT-A and the ShT-B was respectively inserted into pGEM-T vector and formed two cloning plasmids; pGEM-ShTA2 and pGEM-ShTB3. The sequences analysis showed that the cloned mature ShT-A and ShT-B genes were fully identical to one published in GenBank, which lays the foundation for the study on expression of recombinant ShT-A,B fragments in E. coli.