2016年淮南市禽流感外环境H9N2病毒基因组特征分析  

Genomic characteristics of H9N2 avian influenza viruses in external environment in Huainan city,2016

作　　者：刘江[1] 何军[2] 曾凡荣[1] 何玢[1] 杨光[1] 余寿杰[1] Liu Jiang;He Jun;Zeng Fanrong;He Bin;Yang Guang;Yu Shoujie(Department of Microbiology Laboratory,Huainan Center for Disease Control and Prevention,Huainan 232033,China;Department of MUrobiology Laboratory,Anhui Provincial Center for Disease Control and Prevention,Hefei 230601,China)

机构地区：[1]淮南市疾病预防控制中心微生物检验科,232033 [2]安徽省疾病预防控制中心微生物检验科,合肥230601

出　　处：《中华微生物学和免疫学杂志》2020年第10期740-747,共8页Chinese Journal of Microbiology and Immunology

基　　金：2017年安徽省卫计委科研计划项目(2017jk005)。

摘　　要：目的分析淮南市2016年2—4月外环境标本中H9N2亚型禽流感病毒基因组特征。方法选取H9N2亚型荧光PCR检测核酸阳性标本(Ct值≤30),经鸡胚分离培养提取RNA,扩增8个基因节段进行全基因序列测定,分析淮南株各基因节段分子特征,构建进化树进化分析。结果淮南市外环境2株H9N2禽流感毒株血凝素(hemagglutinin,HA)基因和神经氨酸酶(neuraminidase,NA)基因与A/Anhui-Lujiang/39/2018/H9N2人源株核苷酸同源性分别为98.2%~98.3%/97.2%~94.9%,氨基酸序列同源性为98.9%~98.8%/99.2%~98.6%,其余6个内源基因与A/Anhui/1/2013/H7N9、A/Anhui/33163/2016/H5N6高度同源;基因进化分析显示,2016年淮南市2株H9N2亚型禽流感毒株为G57基因型,淮南市2株H7N9分离株、安徽人感染A/Anhui/1/2013/H7N9和A/Anhui/33163/2016/H5N6内源基因均为G57-like基因型;HA蛋白受体结合域氨基酸S132D、K138T、T189D、V/A190T、Q226L变异,NA茎区缺失了"TEI"序列,H274Y、R292K、N294S耐药位点未发生变异,PA基因I550L,PB1基因I368V,PB2基因I504V,NS1基因P42S,M1基因N30D、T215A,M2基因耐药S31N位点均发生突变。结论淮南市活禽市场H9N2病毒与人感染H9N2安徽株A/Anhui-Lujiang/39/2018/H9N2高度同源,处于同一进化分支,均为G57基因型,可提供内源基因与人感染H7N9、H5N6亚型禽流感病毒重组;HA受体结合域氨基酸位点、NA茎区缺失序列、聚合酶活性增加,均加强病毒感染人类的能力,M2离子通道抑制剂(金刚烷烃类)耐药,NA抑制剂(磷酸奥司他韦)仍为敏感药物。Objective To analyze the genomic characteristics of H9N2 subtype avian influenza virus in external environmental specimens collected in Huainan city from February to April,2016.Methods Specimens positive for H9N2 nucleic acid(Ct value≤30)were screened by fluorescent PCR and cultivated in chicken embryos to extract RNA.Eight gene segments were amplified and analyzed with whole genome sequencing.The molecular characteristics of each gene segment of Huainan strains were analyzed.A phylogenetic tree was constructed based on the sequences.Results The hemagglutinin(HA)and neuramidinase(NA)genes of two Huainan H9N2 avian influenza strains and the human-derived strain A/Anhui-Lujiang/39/2018/H9N2 shared the homology of 98.2%-98.3%and 97.2%-94.9%in nucleotide and 98.9%-98.8%and 99.2%-98.6%in amino acid.The other six endogenous genes were highly homologous to those of the A/Anhui/1/2013/H7N9 and A/Anhui/33163/2016/H5N6 strains.The phylogenetic tree showed that two H9N2 subtype avian influenza strains isolated in Huainan city in 2016 belonged to G57 genotype,and the endogenous genes of two Huainan H7N9 isolates and human-derived A/Anhui/1/2013/H7N9 and A/Anhui/33163/2016/H5N6 strains were G57-like genotype.Amino acid mutations in the HA protein receptor binding domain including S132D,K138T,T189D,V/A190T and Q226L were detected.The"TEI"sequence was deleted from the NA stem region.Amino acid mutations associated with drug resistance including H274Y,R292K and N294S were not detected in the isolates,but they carried the mutations of I550L in PA gene,I368V in PB1 gene,I504V in PB2 gene,P42S in NS1 gene,N30D and T215A in M1 gene and S31N in M2 gene.Conclusions The two H9N2 viruses isolated in the live poultry market in Huainan city were highly homologous to the A/Anhui-Lujiang/39/2018/H9N2 strain isolated from humans.The three strains were within the same evolutionary branch and belonged to G57 genotype.The endogenous genes of the two H9N2 viruses could recombine with H7N9 and H5N6 subtype avian influenza viruses that caused hu

关 键 词：H9N2 禽流感 PCR 外环境 HA NA 

分 类 号：S852.65[农业科学—基础兽医学] R373.13[农业科学—兽医学]