一株鸭源H1N6亚型禽流感病毒的分离鉴定及HA和NA基因序列分析

Isolation,Identification and Genetic Analysis of HA and NA Genes of H1N6 Subtype Avian Influenza Virus

为了解禽流感病毒(AIV)在广西中越边境地区的流行情况,本研究在该地区活禽市场开展禽流感病原监测。监测过程中分离鉴定出1株H1N6亚型禽流感病毒,命名为A/Duck/Guangxi/F01/2016(H1N6),对其HA和NA基因进行序列测定,并与GenBank中下载的相关参考序列进行比对和遗传进化分析。结果显示,分离株HA基因与A/sparrow/Guangxi/GXs-1/2012(H1N2)的核苷酸同源性最高(96.9%),NA基因与A/Pavo cristatus/Jiangxi/JA1/2016(H5N6)的核苷酸同源性最高(98.2%)。HA基因裂解位点氨基酸序列为PSIQSR↓GLF,符合低致病性禽流感病毒分子特征;与部分N6亚型禽流感病毒一样,分离株NA基因有11个氨基酸缺失。此外,本研究还对分离毒株的受体亲和性进行了测定,结果显示该病毒优先结合唾液酸α-2,3-Gal受体。本研究结果表明A/Duck/Guangxi/F01/2016(H1N6)是一株重组低致病性禽流感病毒。

In order to understand the epidemic situation of avian influenza virus（AIV）in Sino-Vietnamese border Guangxi,we carried out surveillance of avian influenza in the live poultry market in this region.A strain of H1N6 subtype AIV A/Duck/Guangxi/F01/2016 was isolated from live-bird market in Guangxi-Vietnam border areas.HA and NA genes were sequenced and the genetic analysis of isolate was made with other sequences available in GenBank.The results indicated that HA gene showed 96.9% nucleotide homology with A/sparrow/Guangxi/GXs-1/2012（H1N2）,and NA gene showed 98.2% nucleotide homology with A/Pavo cristatus/Jiangxi/JA1/2016（H5N6）.The sequence analysis of HA gene showed that the virus was categorized as low pathogenic AIV,with the typical HA gene cleavage site of PSIQSR↓GLF.As the same with other N6 isolates,there were 11 amino acids missing.In addition,the receptor affinity of the isolate was also tested in this study.The result showed that the virus preferentially bind to the sialic acidα-2,3-Gal receptor.These data indicated that A/Duck/Guangxi/F01/2016 could be low pathogenic AIV and recombinant from different subtype of AIV.