不同耐热性新城疫病毒株全基因组比较研究

Comparative study on complete genomes of different heat resistant Newcastle disease virus strains

耐热新城疫病毒分子生物学特性研究对于新城疫的防控具有重要意义。从GenBank中检索获得所有已测序的新城疫病毒耐热株全基因组序列和不耐热LaSota株全基因组序列,分别从基因组核酸、结构蛋白氨基酸水平以及囊膜蛋白二级结构、功能位点变化等方面进行生物信息学比较。结果表明:耐热株全基因组序列GC含量略高于不耐热株,基因组中GC分布不均衡,靠近基因组3'端存在GC含量较高区域。耐热株结构蛋白氨基酸组成存在极性氨基酸、杂环族氨基酸以及脯氨酸偏高的现象。耐热株F蛋白理论pI值和不稳定指数均小于不耐热株,二级结构中螺旋区域扩大,折叠区域变小,而HN蛋白理论pI值小于但不稳定指数大于不耐热株,二级结构中螺旋与折叠区域均扩大,且比不耐热株多1个α螺旋。

The study on molecular biology of Newcastle disease virus（NDV） heat resistant（HR） strains is of great significance to the prevention and control of Newcastle disease.The complete genome sequences of all NDV HR strains and thermolabile strain LaSota were retrieved from GenBank.The compositions of nucleic acid of genome and amino acid of structural protein and the secondary structure and functional sites of capsule membrane protein were compared by bioinformatic methods.The GC content of complete genome of the HR strains was slightly higher than that of the thermolabile strain LaSota,and the GC distribution in the genome was unbalanced,and there was a higher GC content area near the 3＇ end of the genome.The composition of polar amino acids,heterocyclic amino acids and proline in the amino acid sequences of HR strain structure protein was higher.The theoretical pI and instability index of F protien of HR strains was lower than thermolabile strain LaSota.F protein secondary structure of the spiral area of HR strains was expanded,but the folding area was smaller.The theoretical pI of HN protein of HR strains was lower than thermolabile strain LaSota.But the instability index of HN protein of HR strains was higher than thermolabile strain LaSota.Both spiral and folding areas of HN protein were expanded and it had one more alpha helix than the thermolabile strain LaSota.