畜牧兽医学报 ›› 2014, Vol. 45 ›› Issue (8): 1342-1347.doi: 10.11843/j.issn.0366-6964.2014.08.020

• 基础兽医 • 上一篇    下一篇

猪流行性腹泻病毒COE基因在毕赤酵母中的表达及生物活性分析

胡青松1,李吕木1*,张小飞2,许发芝1,丁小玲1,徐延伟2,丁维民3   

  1. (1.安徽农业大学 动物科技学院,合肥 230036;2.南京天邦生物科技有限公司,南京 211102;3.安徽安泰农业集团,广德 242200)
  • 收稿日期:2014-01-22 出版日期:2014-08-23 发布日期:2014-08-22
  • 通讯作者: 李吕木(1956-),男,安徽和县人,研究员,博士,博士生导师,主要从事动物营养与饲料科学研究,E-mail:llm56@ahau.edu.cn
  • 作者简介:胡青松(1987-),男,江苏沛县人,硕士生,主要从事猪饲料与营养研究,E-mail:963293490@qq.com
  • 基金资助:

    安徽省生猪产业技术体系(2012)

Expression of Porcine Epidemic Diarrhea Virus COE Gene in Pichia pastoris and Bioactivity Analysis of the Recombinant Protein

HU Qing-song1,LI Lyu-mu1*,ZHANG Xiao-fei2,XU Fa-zhi1,DING Xiao-ling1,XU Yan-wei2,DING Wei-min3   

  1. (1.College of Animal Science and Technology,Anhui Agricultural University,Hefei 230036,China;2.Nanjing Tianbang Bio-Industry CO.,LTD,Nanjing 211102,China;3.Anhui Antai Agricultural Group CO.,LTD,Guangde 242200,China)
  • Received:2014-01-22 Online:2014-08-23 Published:2014-08-22

摘要:

 旨在利用毕赤酵母表达系统表达猪流行性腹泻病毒(PEDV)COE蛋白,及研究COE蛋白免疫小鼠后产生抗体的中和病毒的能力。根据PEDV S糖蛋白基因设计引物,取患猪流行性腹泻病(PED)的仔猪肠道组织,抽提PEDV的总mRNA,进行RT-PCR扩增,获得PEDV部分保护性抗原基因(COE基因)片段。进一步将COE基因导入毕赤酵母表达载体,构建毕赤酵母表达质粒pPIC9K-COE重组质粒,并电转化入酵母感受态细胞GS115中,筛选高拷贝阳性重组菌进行诱导表达。利用SDS-PAGE和Western blot分析重组蛋白及其免疫原性,病毒中和试验评价重组蛋白免疫小鼠后血清抗体的病毒中和能力。RT-PCR扩增获得大小为530 bp的PEDV COE基因,该基因在毕赤酵母表达载体中能够正确表达,SDS-PAGE结果显示毕赤酵母表达的COE蛋白大小在27 ku左右,分泌表达量约30 mg•L-1。Western blot表明PEDV COE重组蛋白具有反应原性。中和试验结果表明,PEDV COE重组蛋白免疫小鼠后血清中特异性抗体具有中和活性,中和效价为1∶36,而对照则小于1∶2。PEDV COE基因可在毕赤酵母中获得分泌表达,且表达的蛋白具有很好的生物学活性。

关键词: 猪流行性腹泻病毒, COE基因, 毕赤酵母表达, 中和活性

Abstract:

The aim of this study was to express the COE protein of porcine epidemic diarrhea virus (PEDV) in Pichia pastoris,and evaluate the neutralizing ability of mices serum after immunization with COE protein.A pair of primers was designed to clone PEDV COE gene,and the PEDV strain was isolated from a clinical sample.The PEDV COE ORF was amplified by RT-PCR.Then the PEDV COE gene was inserted into pPIC9K,and acquared the recombinant plasmid,pPIC9K-COE.After the pPIC9K-COE was linearized by SacⅠand transformed into P.pastoris GS115 by electroporation,the high copy positive recombinant bacteria were screened for inducible expression,which was induced by addition of methanol.SDS-PAGE and Western blot were conducted to analyze the recombinant protein and its immunogenicity.The neutralizing ability of mice serum after immuned with the recombinant PEDV COE was analyzed by virus neutralization test.An 530 bp gene, PEDV COE was amplified by RT-PCR,and the PEDV COE protein were expressed in P.pastoris.The result of SDS-PAGE showed that the 27 kDa PEDV COE protein was expressed in P.pastoris GS115,and the concentration was 30 mg•L-1.Western blot analysis of the PEDV COE protein proved that the immunogenicity of the recombinant protein.And the virus neutralization test result showed that the sera from mice immunized with the recombinant protein possess neutralizing activity,and the neutralization titer was 1:36,while the control was less than 1:2.The results presented here demonstrate that PEDV COE protein can be correctly expressed in P.pastoris,and it has better biological activity.

Key words: porcine epidemic diarrhea virus, COE gene, Pichia pastoris expression, neutralizing activity

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