丙型肝炎病毒NS3蛋白酶结构域在昆虫细胞中的表达及鉴定  

Expression and characterization of hepatitis C virus NS3 protease domain in insect cells

作　　者：杜桂鑫[1] 侯利华[1] 王海涛[1] 

机构地区：[1]军事医学科学院微生物流行病研究所应用分子生物学实验室,北京100071

出　　处：《中华传染病杂志》2002年第1期10-13,共4页Chinese Journal of Infectious Diseases

基　　金：国家自然科学基金资助项目 ( 396 30 0 2 0 )

摘　　要：目的　利用杆状病毒 昆虫细胞表达系统制备丙型肝炎病毒 (HCV)丝氨酸蛋白酶结构域 (proteasedomain)的重组蛋白。方法　构建含有HCV丝氨酸蛋白酶结构域基因的杆状病毒转移载体 pFBCNS3N ,转化大肠杆菌DH10Bac进行转座 ,提取重组Bacmid用Lipofectamine法转染昆虫细胞Sf9包装成重组杆状病毒。用重组杆状病毒感染昆虫细胞进行蛋白表达 ,用SDS PAGE电泳和免疫印迹实验分析表达情况 ;利用去垢剂十二烷基肌酸钠溶解重组蛋白后以Ni NTAagrose柱亲和纯化重组蛋白 ;以重组蛋白NS5ab(包含NS5A羟基端部分和NS5B氨基端部分的重组蛋白 )为底物检测丝氨酸蛋白酶的酶切活性 ;以间接ELISA法分析重组蛋白的抗原性。结果　HCV丝氨酸蛋白酶结构域基因在昆虫细胞中获得高水平表达 ;重组蛋白能够部分溶解于含有去垢剂十二烷基肌酸钠的缓冲液 ;从 5× 10 7细胞中总共获得 0 .2mg重组蛋白 ,纯度大于 90 %;重组丝氨酸蛋白酶能够将NS5ab切割成两个片段 ;血清学实验证实该蛋白抗原性很好。结论　昆虫细胞表达的HCV丝氨酸蛋白酶结构域为膜结合型蛋白 ,具有良好的酶学活性以及抗原性。Objective To produce the recombinant NS3 protease of the hepatitis C virus in insect cells. Methods The gene of HCV serine proteinase domain which encodes 181 amino acids was inserted into pFastBacHTc and the recombinant plasmid pFBCNS3N was transformed into DH10Bac competent cells for transposition. After the recombinant bacmid had been determined to be correct by both blue-white colonies and PCR analysis, the isolated bacmid DNAs were transfected into Sf9 insect cells. The bacmid DNA was verified to replicate in insect cells and package into baculovirus particles via PCR and electronic microscope analysis. The insect cells infected by recombinant baculovirus were determined by SDS-PAGE and Western-blot assays. The recombinant protein was soluted in N-Lauryl Sarcosine Sodium (NLS) and purifed by metal-chelated-affinity chromatography, then the enzymatic activity was measured with the protein substrate NS5ab and the antigenicity of recombinant protease was determined by enzyme-linked immunoabsorbent assay. Results The HCV NS3 protease domain was expressed in insect cells at high level and it was partially resolved in NLS;Totally 0.2 mg recombinant serine proteinase domain with high purity was obtained by metal-chelated-affinity chromatography from 5×10 7 cells and both enzymatic activity and antigenicity of the protein were proven to be good. Conclusion The recombinant HCV NS3 protease expressed in insect cells is a membrane-binding protein with good enzymatic activity and antigenicity.

关 键 词：丙型肝炎病毒 丝氨酸蛋白酶 昆虫细胞 去垢剂 

分 类 号：R373.2[医药卫生—病原生物学]