猪传染性胃肠炎病毒纤突S蛋白干酪乳杆菌表达载体系统的构建

根据猪传染性胃肠炎病毒(TGEV)纤突(S)蛋白的全基因序列及表达载体质粒的基因融合特点,设计一对引物,进行PCR,获得含有TGEV S基因4个主要抗原位点的约2000 bp目的片段,将其分别与表达载体质粒pPG611.1和pPG612.1进行连接,通过电转化进入宿主菌Lacto-bacillus casei393细胞内,通过质粒提取、PCR鉴定、酶切鉴定和序列测定分析,表明TGEV S基因已成功插入到表达载体质粒中,获得了TGEV S蛋白干酪乳杆菌表达载体系统。

Construction of expression system of porcine transmissible gastroenteritis coronavirus spike glycoprotein in Lactobacillus casei

Lactobacillus casei was selected as a bacterial carrier for the expression of porcine transmissible gastroenteritis coronavirus(TGEV) spike glycoprotein S.The gene of S Glycoprotein was cloned into the Lactobacillus casei vectors pPG611.1 and pPG612.1.An approximately 2 000 bps fragment of TGEV gene S that encompasses all the four major antigenic domains critical for neutralization was transformed into Lactobacillus casei 393 by electroporation,resulting in recombinant plasmids pPG 611.1-Sa and pPG 612.1-Sa.The recombinant plasmids were detected by plasmid extraction,PCR,restriction enzymes digest and sequences analysis,the result indicated that TGEV S gene has inserted into the expression vectors and achieved Lactobacillus casei expression systems.It has elected the base for the expression of TGEV S protein in Lactobacillus casei and the production of oral vaccination.