广西中越边境口岸地区1株乙型脑炎病毒全基因组特征分析  

Analysis of the whole genome of a JEV strain isolated from the area of the Sino-Vietnamese border port in Guangxi

作　　者：梁亮[1] 陈世毅[1] 农长挥 韦一知[1] 邓丽丽[1] 马宇燕[1] 韦敬航[1] 秦月[1] 刘巍[1] LIANG Liang;CHEN Shi-yi;NONG Chang-hui;WEI Yi-zhi;DENG Li-li;MA Yu-yan;WEI Jing-hang;QIN Yue;LIU Wei(Guangxi Center for Disease Control and Prevention,Nanning,Guangxi 530028,China;Jingxi Center for Disease Control and Prevention)

机构地区：[1]广西壮族自治区疾病预防控制中心,广西南宁530028 [2]靖西市疾病预防控制中心

出　　处：《中国病原生物学杂志》2021年第7期841-844,849,共5页Journal of Pathogen Biology

基　　金：“一带一路”重要病媒生物携带病原体研究项目(No.2018ZX10101002-002);广西壮族自治区卫生和计划生育委员会自筹经费课题(No.Z20180986)。

摘　　要：目的对在广西中越边境口岸地区分离的乙型脑炎病毒株Jc19095zj的全基因组进行测定和分析,了解其结构及与其他毒株的进化关系和抗原变异情况。方法采用PCR方法分段扩增Jc19095zj的全基因组并测序,利用Genestudio软件拼接毒株的全基因组序列,利用MegaⅩ软件构建全基因组和E基因的系统进化树,采用Bioedit 7.0软件比较核苷酸及氨基酸序列的差异性。结果 Jc19095zj基因组总长10 965个核苷酸,共编码3 432个氨基酸;系统进化树显示,Jc19095zj与广东GⅠb亚型毒株(MH184573)的亲缘关系较近,与越南株90VN70(1990年)处于同一大分支上,而广西本地毒株131V(2007年)在另一个不同的大分支上。E基因系统进化树显示,该毒株与4株近期引起疫情爆发的毒株在同一个分支上。比较全基因组核苷酸序列的同源性,Jc19095zj与进化树中23株JEV毒株的同源性为78.9%~99.1%,其中与GⅠb毒株的同源性为97.9%~99.1%。该毒株与疫苗株SA14-14-2核苷酸差异率为11.5%,氨基酸差异率为2.0%。进一步分析E蛋白的氨基酸位点,Jc19095zj和4株引起乙脑疫情爆发的JEV毒株均与疫苗株SA14-14-2之间存在14个共同的差异位点,但与引起乙脑疫情爆发的4个毒株之间不存在差异。结论 Jc19095zj属于GⅠb亚型,推测目前广西流行株JEV存在GⅠ和GⅢ两种基因型,其中GⅠ型为优势基因型,且决定Jc19095zj毒力和抗原性的关键位点未明显改变,因此疫苗株SA14-14-2理论上对该毒株引起的感染仍具有保护力。Objective To sequence and analyze the whole genome of the JEV strain Jc19095 zj isolated from the area of the Sino-Vietnamese border port in Guangxi in order to determine its structure, evolutionary relationship to other strains, and antigenic variation. Methods Fragments of the whole genome of the Jc19095 zj strain were amplified using PCR, and sequenced fragments were assembled to obtain the whole genome using the software Genestudio software. Phylogenetic trees for the whole genome and the E gene were constructed using Mega Ⅹ, and nucleotide and amino acid sequences of Jc19095 zj were compared to those of other strains using Bioedit 7.0. Results The length of genome of the Jc19095 zj strain was 10,965 Nt, and it encoded a polyprotein of 3,432 amino acids. A phylogenetic tree based on the whole genome of JEV indicated that the Jc19095 zj strain was most closely related to the Guangdong strain(MH184573), which belongs to the GⅠb genotype. The Jc19095 zj strain is located on the same evolutionary branch as the Vietnam strain 90 VN70(1990), but the local strain 131 V(2007) is located on a different branch. Moreover, a phylogenetic tree based on the E gene indicated that the Jc19095 zj strain and 4 strains that recently caused outbreaks of Japanese encephalitis are located on the same evolutionary branch. A comparison of the homology of nucleotide sequences of the whole genome indicated that the similarity of Jc19095 zj to 23 JEV strains in the evolutionary tree ranged from78.9% to 99.1%. The similarity of that strain to strains of the GIb genotype ranged from 97.9% to 99.1%. The difference in nucleotides between Jc19095 zj and the vaccine strain SA14-14-2 was 11.5%, and the difference in amino acids was 2.0%. Further analysis of the amino acid sites of the E protein indicated that the Jc19095 zj strain and the 4 JEV strains that recently caused outbreaks of Japanese encephalitis differed from the vaccine strain SA14-14-2 at 14 sites: E107, E129, E138, E176, E177, E222, E244, E264, E279, E315, E327, E366, E439

关 键 词：乙型脑炎病毒 全基因组 系统进化分析 中越边境口岸 

分 类 号：R373.31[医药卫生—病原生物学]