【摘要】 目的分析安徽省2013年分离的5株人感染H7N9禽流感病毒全基因组特征。方法从美国国家生物技术信息中心(NCBI)和全球禽流感基因共享数据库(GISAID)中下载具有代表性的H7N9、H7N3、H7N7和H9N2等毒株序列,运用分子生物信息学软件分析病毒全基因组特征。结果我省流行的H7N9病毒HA基因与A/duck/Fujian/6390/2010(H7N3)相似度最高,NA基因与A/northern shoveler/Hong Kong/MPL133/2010(H2N9)株相似度最高,6个内部基因片段与中国北京、香港、湖南、江苏地区分离的H9N2毒株相似度接近。氨基酸序列比对发现NS1蛋白218~230位氨基酸缺失、M2蛋白的N31S突变、HA蛋白的G186V、Q226L突变以及NA蛋白69~73位的删除,并且我省人感染H7N9病毒均带有PB2的E627K突变,同时PA-100A、PA-356R、PA-409N这些易感人类的特征氨基酸也在本次流行的H7N9病毒中发现;此外HA蛋白裂解位点仅有1个碱性氨基酸、糖基化位点高度保守以及未发现NA蛋白R294K突变也是我省H7N9病毒主要特征。结论我省人感染H7N9病毒与中国其他省份流行株高度同源,该病毒获得跨种传播、毒力增强、耐药等能力均与病毒蛋白功能域有关。更多还原

【Abstract】 To understand genomic features of 5avian influenza virus A(H7N9)cases isolated from Anhui Province,China,the genome sequences of influenza virus H7N9,H7N3,H7N7 and H9N2subtypes were downloaded from database of NCBI(The National Center for Biotechnology Information)and GISAID(Global Initiative on Sharing All Influenza Data).Genomic features were analyzed with molecular bioinformatics software.In H7N9,the highest homology was found in HA gene with A/duck/Fujian/6390/2010(H7N3),and NA gene with A/northern shoveler/Hong Kong/MPL133/2010(H2N9).Six genes encoding for internal proteins shared high identity with H9N2 avian influenza isolated from Beijing,Hong Kong,Hunan,and Jiangsu in China.The amino acid sequence alignment result showed that 218 to 230amino acids were deleted in NS1;N31S was mutated in M2;G186Vand Q226 Lwere mutated in HA;69to 73 amino acids were deleted in NA.In addition,E627 K was mutated in PB2 in H7N9virus isolated from human.A few amino acids with human features including PA-100 Aand PA-356R;PA-409 Nwere also found in this H7N9 virus.The other main features included single basic amino acid of HA cleavage sequence,high conservation of the glycosylation sites,and non-mutation of R294 Kin NA protein.In conclusion,high homology was existed in avian influenza virus(H7N9)between Anhui Province and other epidemic provinces.The characterization of cross-species transmission,increased virulence,and drug-resistance were related with functional domains of viral proteins.更多还原