一株养殖场乌鸡源H7N9流感HA基因序列分析

Analysis of hemagglutinin genes of H7N9 virus isolated from silkie chicken in a farm

H7N9流感的宿主主要是鸡,本研究对1株来源于养殖场乌鸡的H7N9流感HA基因序列进行测定,分析其分子特征,发现该毒株与当地流行的毒株核苷酸相似性高达98.7%,说明本次养殖场的乌鸡感染事件由本地区流行毒株引起.该病毒HA蛋白潜在的糖基化位点与其他参考毒株一至,均为5个,分别位于30-32、46-48、249-251、421-423、493-495位氨基酸.裂解位点为PEIPKG/RGLF,呈弱毒的分子特征.受体结合位点中,235位Q(H3编码226位),仍保持禽源与α-2,3 Gal受体结合的特征,但195位(H3编码186位)与169(H3编码160位)位均出现了适应人与α-2,6 Gal受体结合的特征.本文为H7N9病毒感染不同宿主后的分子特征的研究提供有益的补充.

Normally,the chicken is the main host of H7 N9 flu. virus,In this study,the HA gene sequence of H7 N9 influenza virus from a silkie chicken breeding farms was detected, and its molecular characteristics were analyzed. It was found that the nucleotide similarity between the strain and the local popular nucleotides was 98.7%,indicating that the infection of this chicken farm is caused by the prevalent strains in this area. The potential glycosylation sites of the virus HA protein were 5 other than those of other reference strains,which were located at 30-32,46-48,249-251,421-423 and 493-495 amino acids,respectively. The cleavage site is PEIPKG/RGLF,which was classified as low pathogenic AIV. In the receptor binding site,235 sit of Q(H3 encoding 226)still retain the characteristics of the binding of avian sources to α-2,3 Gal receptor,but 195 sit(H3 encoded 186 sit)and 169(H3 coding 160 sit)all appear to be adapted to the combination of human and α-2,6 Gal receptors. This article provides a useful supplement to the study of the molecular characteristics of H7 N9 virus infected different hosts.