中文摘要：

为了进一步明确副粘病毒Tianjin株的来源和种系进化地位,探讨其高致病性的机制。对Tianjin株NP、P、M及L蛋白进行了生物信息学分析。进化树显示：Tianjin株属于副粘病毒亚科呼吸道病毒属,且很可能为仙台病毒新的基因型。相似性比较表明,P蛋白变异最大,相似性仅为78.7%～91.9%;L蛋白相似性最高,为96.0%～98.0%。序列比对显示：NP蛋白氨基酸序列中存在15个独特的变异位点,P蛋白存在29个,M蛋白存在6个,L蛋白存在29个。这些独特变异位点的存在很可能是导致Tianjin株在宿主来源和致病特点等方面与已知仙台病毒株具有较大差异的原因。

英文摘要：

In order to demonstrate the taxonomic position of paramyxovirus Tianjin strain and explore its mechanism of pathogenesis. Bioinformatics methods were used to analyze the deduced amino acid sequences of NP, P, M, and L protein of Tianjin strain. Phylogenetic analysis based on NP, P, M, and L protein sequences demonstrated that Tianjin strain belonged to the genus Respirovirus, in the subfamily Paramyxovirinae and most likely a new genotype of Sendai virus. Sequence similarities comparisons indicated that Tianjin strain P protein was poorly conserved, sharing only 78.7%-91.9% amino acid identity with 6 known Sendai viruses, while L protein was the most conserved, having 96.0%-98.0% amino acid identity with other Sendai viruses. Multiple-sequence alignments of Tianjin strain NP, P, M, and L protein with those of 6 known Sendai viruses showed that Tianjin strain possessed a lot of unique amino acid substitutions in protein sequences, 15 in NP, 29 in P, 6 in M, and 29 in L. The presence of these unique amino acid substitutions suggests that Tianjin strain maybe has a significant difference in host or pathological characteristics from the known Sendai viruses.