Tosh C, Murugkar H V, Nagarajan S, Tripathi S, Katare M, Jain R, Khandia R, Syed Z, Behera P, Patil S, Kulkarni D D, Dubey S C
High Security Animal Disease Laboratory, Indian Veterinary Research Institute, Anand Nagar, Bhopal, India.
Virus Genes. 2011 Feb;42(1):10-5. doi: 10.1007/s11262-010-0534-z. Epub 2010 Oct 16.
This study reports the genetic characterization of highly pathogenic avian influenza (HPAI) virus (subtype H5N1) isolated from poultry in West Bengal, India. We analyzed all the eight genome segments of two viruses isolated from chickens in January 2010 to understand their genetic relationship with other Indian H5N1 isolates and possible connection between different outbreaks. The hemagglutinin (HA) gene of the viruses showed multiple basic amino acids at the cleavage site, a marker for high virulence in chickens. Of greatest concern was that the viruses displayed amino acid substitution from serine-to-asparagine at position 31 of M2 ion channel protein suggesting emergence of amantadine-resistant mutants not previously reported in HPAI H5N1 outbreaks in India. Amino acid lysine at position 627 of the PB2 protein highlights the risk the viruses possess to mammals. In the phylogenetic trees, the viruses clustered within the lineage of avian isolates from India (2008-2009) and avian and human isolates from Bangladesh (2007-2009) in all the genes. Both these viruses were most closely related to the viruses from 2008 in West Bengal within the subclade 2.2.3 of H5N1 viruses.
本研究报告了从印度西孟加拉邦家禽中分离出的高致病性禽流感（HPAI）病毒（H5N1亚型）的基因特征。我们分析了2010年1月从鸡中分离出的两种病毒的所有八个基因组片段，以了解它们与其他印度H5N1分离株的遗传关系以及不同疫情之间的可能联系。这些病毒的血凝素（HA）基因在裂解位点显示出多个碱性氨基酸，这是鸡高致病性的一个标志。最令人担忧的是，这些病毒在M2离子通道蛋白的第31位显示出从丝氨酸到天冬酰胺的氨基酸替代，这表明出现了印度HPAI H5N1疫情中以前未报道过的金刚烷胺抗性突变体。PB2蛋白第627位的氨基酸赖氨酸突出了这些病毒对哺乳动物构成的风险。在系统发育树中，所有基因中的病毒都聚集在来自印度（2008 - 2009年）的禽类分离株以及来自孟加拉国（2007 - 2009年）的禽类和人类分离株的谱系内。这两种病毒与H5N1病毒2.2.3亚分支中2008年来自西孟加拉邦的病毒关系最为密切。
