中国分离乙脑病毒与灭活疫苗株(P3株)E基因差异分析

目的 分析我国近年来从蚊虫及患者标本中分离的乙脑病毒与灭活疫苗株（P3株）之间在E基因区段核苷酸及氨基酸差异。方法 从GenBank中获取相应乙脑病毒株E基因区段核苷酸序列，通过Clustal X（1．8）、DNASTAR、GENEDOC（3．2）等生物学软件进行分析。结果 P3株与福建分离株之间核苷酸同源性在98．3％-98．5％之间、氨基酸同源性在98．2％-98．6％之间；P3株与上海分离株之间核苷酸同源性在88．0％-88．5％之间、氨基酸同源性在98．0％-98．4％之间。E基因区段500个氨基酸中P3株与所有新分离乙脑病毒株之间共存在19个位点的差异，其中在E-76、E-306、E-408处所有新分离毒株与P3株存在共同的差异；在E-160、E-487处福建分离株与P3株存在共同差异；上海分离株与P3株在E-129、E-222、E-227、E-366存在共同差异。结论 上海蚊虫中分离的Ⅰ型乙脑病毒和福建省脑炎患者中分离的Ⅲ型乙脑病毒与P3株在E基因的部分氨基酸位点存在差异，但均不处在影响病毒生物学特性的关键位点。

Comparison of nucleotide and deduced amino acid sequences of E gene of the newly isolated Japanese encephalitis virus strains and inactivated vaccine strain P3

BACKGROUND: To analyze the difference of nucleotides and deduced amino acids sequences E gene between the newly isolated Japanese encephalitis (JE) virus strains from mosquitoes or patients and P3 strain. METHODS: The E gene sequences of corresponding strains of JE virus were obtained from GenBank. Computer analyze of nucleic acid data and deduced amino acid sequence were accomplished using the Clustal X (1.8), DNASTAR, GENEDOC (3.2) programs. RESULTS: The result showed that compared with the Fujian strains and P3 strain the nucleotide sequence homology was up to 98.3%, and the amino acid sequence homology was up to 98.2%, respectively. Compared with the Shanghai strains and P3 strain, the nucleotide sequence differences were 12%, and the amino acid sequence homology was up to 98.2%, respectively. Compared with P3 strain, there were nineteen amino acid variations in E gene of all the newly isolated strains. Between P3 and all the newly isolated JE virus strains, there are three common variations at E-129, E-222, E-366. And two common variations E-160 and E-487 were found only in Fujian strains, common variations at E-129, E-222, E-227, E-366 in Shanghai strains. CONCLUSION: There are some differences between P3 strain and JE viruses which were isolated from mosquitoes belonging to genotype I in Shanghai and from patients belonging to genotype III from Fujian province. But these variations are not in the important locations affecting the biological characteristic of the viruses.