【摘要】 对鸽源冠状病毒PSH株纤突蛋白基因进行了RT-PCR扩增、克隆和测序。结果表明,PSH株S基因由3 504个核苷酸组成,编码1条由1 167个氨基酸残基组成的多肽。S基因编码产物裂解后形成的S1和S2亚单位分别由541和626个氨基酸残基组成。PSH株S蛋白切割识别位点为精氨酸-精氨酸-苯丙氨酸-精氨酸-精氨酸(RRFRR),与多数鸡传染性支气管炎病毒(IBV)切割识别位点相似(RRF/SRR)。与GenBank中其他冠状病毒毒株S基因的推导氨基酸序列相比较,PSH株与IBV参考毒株的同源性为79.3%~99.6%,而与其他冠状病毒包括火鸡蓝冠病病毒和SARS病毒的同源性均小于37.8%。表明,鸽源冠状病毒PSH株属于第3抗原群冠状病毒,且与IBV亲缘关系较近。更多还原

【Abstract】 Spike glycoprotein gene of PSH strain of coronavirus of pigeon origin was amplified by RT-PCR,cloned,sequenced and compared with the published spike genes sequences of coronaviruses from GenBank.Results showed that the S gene of PSH strain was 3504 nucleotides in length,encoding a polypeptide of 1167 amino acids.The cleavage site sequence of the S glycoprotein of the PSH strain contained five consecutive basic amino acids,namely,Arg-Arg-Phe-Arg-Arg(RRFRR),which was similar to the majority of avian infectious bronchitis virus(IBV) strains.The deduced S1 and S2 proteins were composed of 541 and 626 amino acids,respectively after S protein was cleaved.A high degree of sequence identity(79.3%-99.6%) was observed in the S glycoprotein sequences between the PSH strain and IBV,but only low similarity(<37.8%) was observed with turkey coronavirus(TCoV) and other mammalian coronaviruses.Based on these findings,the virus was tentatively identified as a member of group 3 coronaviruses which has closer relationship with the IBV strains.更多还原