柯萨奇病毒B组3型天津分离株的全基因组特征分析  

Whole genomic features analysis of coxsackievirus B3 strains isolated in Tianjin

作　　者：庄志超 雷玥 胡华清 谭昭麟 刘杨 田宏 李晓燕 ZHUANG Zhichao;LEI Yue;HU Huaqing;TAN Zhaolin;LIU Yang;TIAN Hong;LI Xiaoyan(Tianjin Key Laboratory of Pathogenic Microorganisms for Infectious Diseases,Tianjin 300011,China)

机构地区：[1]天津市传染病病原微生物重点实验室,天津300011

出　　处：《中国热带医学》2023年第10期1114-1121,共8页China Tropical Medicine

摘　　要：目的对天津市柯萨奇病毒B组3型(Coxsackievirus B3,CVB3)分离株进行基因分型及全基因组特征分析,完善天津市CVB3病毒进化信息,为相关疾病的监测预警提供依据。方法对在天津分离到的5株CVB3毒株提取病毒RNA,通过反转录酶-聚合酶链锁反应(reverse transcription-polymerase chain reaction,RT-PCR)扩增病毒全基因组序列,使用二代测序方法进行全基因组序列测定,对病毒全基因组序列进行系统进化与重组分析。结果本研究中5株CVB3毒株开放阅读框1(open reading frame,ORF)均含有6555个核苷酸,编码2185个氨基酸,ORF2均由编码68个氨基酸大小的序列构成。核苷酸序列相似性为78.3%~100%,氨基酸序列相似性为95.7%~100%。而5株病毒与病毒原型株相比,核苷酸序列相似性为78.2%~79.1%,氨基酸序列相似性为94.9%~95.3%。5株病毒均在VP2蛋白上出现T151A位点突变,此外脑炎分离株还存在VP2蛋白K158E位点突变,1株生活污水分离株在5'非编码区存在C234T突变。5株病毒分属2个不同基因型,其中2016年的脑炎分离株属于D基因型,而2021年的外环境生活污水分离株属于E基因型,这也是我国北方地区首次报道E基因型CVB3。本研究的CVB3毒株在非结构蛋白区可能存在重组事件,其中脑炎分离株可能与1株柯萨奇病毒B组5型(Coxsackievirus B5,CVB5)毒株发生重组,而生活污水分离株与1株埃可病毒18型(ECHO virus 18,E18)毒株存在重组事件。结论天津市CVB3分离株分属D与E基因型,病毒基因组在非结构蛋白区可能存在重组事件。外环境生活污水中CVB3病毒基因组分析结果提示天津市人群有CVB3感染存在,同时其流行优势基因型可能发生了转变。Objective To genotype and analyze whole genomic features of Coxsackievirus B3(CVB3)isolated in Tianjin,to improve evolution information of CVB3 virus in Tianjin,and to provide basis for surveillance and early warning of related diseases.Methods Viral RNA was extracted from five CVB3 strains isolated in Tianjin,whole genome sequence of the virus was amplified by RT-PCR and sequenced by next-generation sequencing method,and phylogenetic and recombinant analysis were carried out.Results The open reading frame 1(ORF)of the five CVB3 strains contained 6555 nucleotides and encoded 2185 amino acids,and ORF2 was composed of sequences encoding 68 amino acids.The nucleotide sequence similarity ranged from 78.3%-100%,and the amino acid sequence similarity ranged from 95.7%-100%.Compared with the CVB3 prototype strain,the nucleotide sequence similarity of the five viruses was between 78.2%-79.1%,and the similarity of amino acid sequences was 94.9%-95.3%.All five viruses exhibited a T151A mutation on the VP2 protein.Additionally,the encephalitis isolate showed a K158E mutation on the VP2 protein,while one of the sewage isolates had a C234T mutation in 5'noncoding region.The five strains belonged to two different genotypes,among which the encephalitis isolate in 2016 belonged to the D genotype,while the sewage isolates in 2021 belonged to the E genotype.This is also the first report of E genotype CVB3 in northern China.The CVB3 strain may have recombinant events in non-structural protein regions,in which encephalitis isolate may recombine with a Coxsackievirus B5(CVB5)strain,while sewage isolates may have recombinant events with a strain of ECHO virus 18(E18).Conclusions The CVB3 isolates in Tianjin belong to D and E genotypes,and recombination events may exist in non-structural protein region of the viral genome.The results of CVB3 virus genome analysis in sewage suggests presence of CVB3 infection in the population of Tianjin,and its epidemic dominant genotype may have changed.

关 键 词：柯萨奇病毒B组3型 天津分离株 全基因组特征 重组 污水监测 

分 类 号：R511[医药卫生—内科学]