新余市甲型流感病毒M基因进化及金刚烷胺类耐药性分析

Analysis on the evolution characteristics of the matrix protein(M) gene and resistance to amantadine of influenza A virus in Xinyu

目的分析新余市2013年-2015年甲型流感病毒M基因进化及金刚烷胺类耐药情况,为临床治疗和疾病防控提供依据。方法随机选择30株甲型流感病毒,经核酸提取、one-step RT-PCR扩增M基因片段和双向序列测定,通过DNAStar5.0和Mage5.0序列分析软件获得有关数据。结果在M基因上,16株H3N2毒株、14株新型H1N1毒株核苷酸序列的同源性分别>99.2%、>98.8%,且与相应的疫苗推荐株高度同源,H3N2毒株与新型H1N1毒株与相应的疫苗推荐株相比较,大部分(13/16)H3N2毒株未发生变异,所有新H1N1毒株均发生1~2个氨基酸替换;30株新余市甲型流感毒株M2蛋白第31位氨基酸位点均由丝氨酸(S)突变为天冬酰胺(N)。结论新余市2013年至2015年甲型流感毒株相同亚型间M基因同源性较高,30株甲型流感毒株均具有金刚烷胺类药物抗性,对流感病毒耐药性问题应该给予重视。

Objective To analyze the evolution characteristics of the matrix M gene and resistance to amantadine of influenza A virus in Xinyu from 2013 to 2015 and provide scientific information for clinical treatment and disease control and prevention of influenza. Methods 30 strains of influenza A virus were randomly selected for detection and viral RNA was extracted. Segments of the M gene were amplified by one-step RT-PCR and then were sequenced bidirectionally. The sequence data obtained were analyzed with the assistant of DNAStar 5.0 and Mage 5.0 software. Results In the M genes,16 strains of the H3 N2 virus and 14 strains of the novel H1 N1 virus had >99.2% and >98.8% nucleotide identity respectively,and all strains kept high degree of sequence homology to their respective vaccine-recommended strains. In comparison with their respective vaccine-recommended strains,most of(13/16) H3 N2 strains did not mutate,but all novel H1 N1 strains had 1 or 2 amino acid substitutions. 30 strains of influenza A virus in Xinyu had serine to asparagine mutation at position 31 of the M2 protein. Conclusion The M genes of influenza A virus strains isolated from Xinyu during 2013 to 2015,there was high homology among the same subtypes. 30 strains of influenza A virus were resistant to amantadine,and should be paid attention to drug-resistantinfluenza virus.