天津市致病毒性脑炎柯萨奇病毒B组5型全基因组序列分析

肠道病毒是我国病毒性脑炎(Viral encephalitis,VE)的主要病原体。本文研究对4株引起VE的天津柯萨奇病毒B组5型(Coxsackievirus B5,CV-B5)分离株进行Illumina MiniSeq高通量测序,并对其全基因组特征、进化及重组特点进行分析。结果提示,4株CV-B5天津分离株的全基因组核苷酸和氨基酸序列同源性分别为84.5%~100.0%和98.1%~100.0%,与国内流行株的全基因组核苷酸序列同源性为83.2%~96.5%,氨基酸序列同源性为96.4%~99.4%。基于全基因组的系统进化分析将CV-B5流行株分为A-D四个基因型,其中天津与国内流行株均属于C基因型。C基因型进一步分为3个进化分支,而天津分离株处在两个不同的分支上。基于基因组各区段序列的系统进化与SimPlot重组分析结果显示,天津分离株15-39N、15-41N与埃可病毒30型(Echovirus 30,E-30)原型株在P3区3B、3C、3D区域均检测到重组信号。本研究有助于了解CV-B5的全基因组特点和重组规律,为相关疾病的防控提供依据。

Complete Genome Analysis of Coxsackievirus B5 Causing Viral Encephalitis Isolated in Tianjin,China

Enterovirus is the major pathogen causing viral encephalitis(VE)in China.Here we reported complete genome sequences of 4 coxsackievirus B5(CV-B5)Tianjin strains associated with VE by Illumina MiniSeq sequencing,and studied their genetic characteristics,evolution and recombination.The homology of the complete genome nucleotides and amino acids among Tianjin strains were 84.5%-100.0%and 98.1%-100.0%,respectively.The homology of complete genome nucleotides and amino acids between Tianjin and domestic strains were 83.2%-96.5%and 96.4%-99.4%,respectively.Phylogenetic analysis indicated that CVB5 strains can be divided into four genotypes A,B,C and D,and all the strains isolated in China belong to genotype C.Genotype C can be further divided into 3 distinct lineages,and 4 Tianjin strains belong to 2 different lineages.The phylogenetic tree and SimPlot analysis indicated that 15-39 N and 15-41 N strain might have recombination event with echovirus 30(E-30)in P3 region.This study will contribute to the understanding of genetic characteristics and recombination variation of CV-B5,and help to provide basic information for control and prevention of disease associated with CV-B5.