新型重配A（H7N9）流感病毒NA基因序列分析

试验旨在分析2013年新型重配A（H7N9）流感病毒分子流行病学特点。作者从GenBank数据库下载不同分离宿主的流感毒株NA全基因序列，应用分子生物学软件进行遗传进化分析。结果显示，2013年新型重配A（H7N9）流感毒株NA蛋白颈部氨基酸发生缺失，其唾液酸结合（HB）位点发生一定程度适应性变化，NA蛋白糖基化位点为7个，NA蛋白酶活性中心未发生变异。与A/Hangzhou/1/2013（H7N9）株中NA片段的核苷酸同源性较高的前10个序列均分离自亚洲5个国家的禽类，同源性达96%以上。至于此次新型重配A（H7N9）流感毒株NA基因是否是禽传给人尚不清楚，还有待进一步研究。

Sequence Analysis of NA Gene of the Novel Reassortment Influenza A (H7N9) Virus

The assay was aimed to analyze the molecular epidemiological character of influenza A (H7N9) virus in 2013. The complete genome sequences of NA of influenza virus strains from different discrete host sources downloaded from the GenBank were analyzed on genetic evolution by DNAStar software in this research. The results showed that, the neck amino acids of NA in influenza A (H7N9) virus in 2013 was deleted; HB site of NA took adaptive changes in certain degrees; the active site of proteases of HA with seven glycosylation sites was unchanged; the top ten high nucleotide homology strains with HA of A/Hangzhou/1/2013(H7N9) had isolated from poultry in five Asian countries, the nucleotide homology was more than 96%. It was not clear whether the NA gene of novel reassortment influenza A (H7N9) virus strains was avian-to-human transmission and needed further study.