法氏囊素在大肠杆菌中的表达及其免疫增强活性  

Expression of Tandem Bursin Genes in Escherichia coli and Its Immune Improvement Activity

作　　者：丁家波[1] 朱鸿飞[2] 赵文明[3] 崔治中[1] 

机构地区：[1]山东农业大学动物科技学院,泰安271018 [2]中国农业科学院生物制品工程技术中心,北京100081 [3]扬州大学动物科学与技术学院,扬州225009

出　　处：《农业生物技术学报》2006年第1期33-37,共5页Journal of Agricultural Biotechnology

基　　金：国家十五重点科技攻关项目(No.2004BA519AZZ)资助

摘　　要：选用大肠杆菌(Escherichiacoli)编码赖氨酸(Lys)、组氨酸(His)和甘氨酸(Gly)的常用密码子按顺序排列成BS基因:5'-AAACACGGT-3'。连续合成10个BS(BS10)串连基因单链及其反向互补链,通过退火使其复性成双链。BS10基因经EcoRⅠ和SalⅠ双酶切后,克隆进表达载体pGEX-6P-1中。获得的重组质粒pGEX-Bur转化大肠杆菌BL21,经IPTG诱导,串连的BS10基因获得了高效表达。表达产物经GST亲和层析和胰酶消化处理后,按适当的浓度和新城疫病毒(NDV)混合,免疫90只30日龄的小白鼠。分别在免疫后第7,14和21天,用血凝抑制试验(HI)测定小鼠血清中NDV的抗体水平,结果加入囊素的实验组比不加囊素的对照组HI平均高出22.5个滴度。同样的实验样品免疫100只8日龄SPF(speclficpathogenfree)鸡,15d后实验组的抗体水平比对照组平均高出20.7个滴度。研究结果证实了用大肠杆菌表达的法氏囊素对小鼠和鸡具有免疫增强的作用。A DNA fragment containing 10 bursin gene tandem repeats （BS10） was synthesized as 5＇- GAATTC（AAACACGGT） 10GTCGAC-3＇, according to the common codons in Escherichia coli. for lysine, histidine and glycin. It was cloned into expression vector pGEX-6p-1 in the open reading frame （ORF） fused to GST. E.coli BL21 was transformed by the recombinant plasmid pGEX-Bur, and the recombinant BS10 fusion protein was purified through the GST-affinity column, then treated with trypsin. Ninety 30-day-old mice and 100 8-day-old specific pathogen free （SPF） chickens were immunized with inactivate New castle disease virus （NDV） mixed with the trypsin-treated BS10. Another group of mice and SPF chickens were immunized with inactive NDV without BS10 as controls. Serum samples of tested mice were collected at 7, 14 and 21, days after immunization, and antibody levels were rifled by hemoagglutinin inhibit assay （HI）. The result showed HI titer of the NDV samples with BS10 was 2^2.5 higher than that of samples without BS10. To chickens, the HI liter of the test group was 20.7 higher than the control 15 days post immunization. In this study, the expressed BS10 displayed significantly enhancement to immunity, it may be a particularly useful vaccine adjuvant.

关 键 词：法氏囊素 基因串连 表达 免疫增强 

分 类 号：S188[农业科学—农业基础科学]