新型甲型H7N9流感病毒神经氨酸酶基因进化分析

目的探讨2013年新型甲型H7N9流感病毒神经氨酸酶(NA)基因的进化,及其编码蛋白重要氨基酸位点的变异情况。方法从美国国家生物技术信息中心(NCBI)数据库和全球禽流感基因共享数据库(GISAID)下载不同年代、不同地区甲型流感病毒N9亚型的NA基因序列,利用MEGA 5.05和BioEdit软件对基因的核苷酸序列和氨基酸序列进行分析。结果 2013年新型甲型H7N9流感病毒NA基因与2010年捷克共和国H11N9禽流感病毒的相似性达到96%;新型流感病毒存在5个氨基酸的缺失;其中1株新型病毒可能的酶活性位点发生了变异。结论 2013年新型甲型H7N9流感病毒的NA基因可能是由H11N9进化而来;氨基酸的缺失可能是造成人感染和较高病死率的原因。

Evolutionary analysis of neuraminidase gene of the novel avian influenza virus A/H7N9

Objective: To investigate the evolutionary characteristics and important amino acid sites of the neuraminidase (NA) gene of the new influenza virus A/H7N9 in 2013. Method: The NA gene sequences of influenza virus A N9 subtype were downloaded from NCBI and GISAID. MEGA 5.05 and Bioedit were used for phylogenetic tree construction and nucleotide/protein sequence analysis. Result: NA genes similarity of the novel influenza virus A/H7N9 in 2013 was around 96% to the avian strain of Czech Republic in 2010. There were 5 amino acid deletions in the new influenza virus. One of the new strains had a variation in potential enzymatic active sites. Conclusion: The NA gene of 2013 new influenza virus may originate from avian H11N9 detected in Czech Republic. The deletion of amino acid might result in human infection and high fatality rate.