1株H6N6亚型禽流感病毒分子遗传特性分析

本研究采用无特定病原体(specific pathogen free，SPF)鸡胚，从某活禽市场环境中分离出1株H6N6亚型禽流感病毒(A/environment/Zhenjiang/zj18/2013，en/zj18)。通过二代测序技术进行全基因组测序，通过BLASTn 进行同源性检索，并采用MEGA5.0软件构建系统发生树。基因进化树分析表明，分离株en/zj18的所有8个基因节段(PB2、PB1、PA、HA、NP、NA、M和NS)均与近年来中国华东地区流行的H6N6亚型禽流感病毒的相应基因位于同一进化分支，与参考株的核苷酸同源性达96.7%～99.6%。分离株en/zj18的HA蛋白裂解位点为PQIETR↓GL，是低致病性禽流感病毒的分子特征。HA蛋白上关键受体结合位点190和228位(按H3亚型的HA蛋白序列排序)氨基酸分别是E和G，理论上更易与α2，3-半乳糖苷唾液酸受体结合。结果提示，需加强活禽市场禽流感病毒的持续监测，从而为有效应对禽流感病毒对公共卫生的持续威胁提供科学依据。

Molecular characterization of one H6N6 subtype avian influenza virus isolated from a live poultry market in Zhenjiang

One H6N6 subtype avian influenza virus 〔A/environment/Zhenjiang/zj18/2013(en/zj18)〕 was isolated from a live poultry market in Zhenjiang in an epidemiological surveillance and was subjected to genome sequencing and further analysis.Next-generation sequencing(NGS)by Illumina MiSeq Platform was used to obtain the complete genome sequence from the isolated virus.MEGA5.0 software was used to align the eight fragments respectively.The phylogenetic and molecular characteristics of the isolate were analyzed by Neighbor-Joining method.BLAST searches demonstrated that the 8 genes(PB2,PB1,PA,HA,NP, NA,M and NS)had 96.7% -99.6% nucleotide identity with the ones on the H6N6 subtype reference viruses circulating in southeast China.The enzyme cleavage site on HA was PQIETR↓GL,which was the typical characteristic of the low pathogenic avian influenza virus(LPAIV).The key HA receptor binding sites were E190 and G228,indicating a preference binding for α2-3-linked sialic acids.The results suggest that it is necessary to strengthen the continuous surveillance of avian influenza A viruses.