羊传染性脓疱病毒湖北分离株CBP二级结构及其细胞表位的预测

PREDICTION OF THE SECONDARY STRUCTURE AND EPITOPES OF CHEMOKINE-BINDING PROTEIN OF ORF VIRUS HUBEI STRAIN

参照GenBank中羊传染性脓疱病毒(Orf virus,ORFV)的毒力因子趋化因子结合蛋白(chemokine-binding protein,CBP)基因的核苷酸序列设计合成1对特异性引物,以羊传染性脓疱病毒湖北分离毒株的DNA为模板,提取总DNA。采用PCR方法特异扩增该基因片段,得到CBP基因序列。通过网络平台的SOPMA服务器和DNAStar软件预测ORFV CBP蛋白的二级结构;综合利用DNAStar软件、二级结构预测及ABCpred方案预测羊ORFV CBP蛋白的B细胞表位;分别采用人工神经网络法(ANNA)和在线程序预测ORFV CBP蛋白的细胞毒性T细胞和辅助T细胞的抗原表位。结果显示,ORFV CBP蛋白的二级结构主要包括α-螺旋、β-转角、无规则卷曲和β-片层4种类型,分别为α-螺旋占24.64%、β-片层占22.14%、β-转角占3.39%、无规则卷曲占49.29%;有7个优势B细胞表位,7个细胞毒性T细胞表位和3个辅助T细胞表位。本研究为ORFV诊断方法的建立、单克隆抗体的制备及表位疫苗的研制提供了理论依据。

According to the published chemokine-binding protein （CBP） gene sequence of Orf virus in the GenBank, a pair of primers were designed and synthesized for amplification in PCR using total DNA of Orf virus Hubei strain as template. The PCR products of the CBP gene were sequenced. Subsequently, the secondary structure of the CBP protein was predicted using the network platform SOPMA server and DNAStar software. The B cell epitopes of the CBP protein were predicted by comprehensive utilization of the DNAStar software, the secondary structure prediction and ABCpred program. The cytotoxic T cell and T helper epitopes of the CBP protein were predicted using the artificial neural network （ANNA） and online program. The results showed that the CBP protein of Orf virus was composed withα-helixes （24.64%）,β-sheet （22.14%）, random coils （49.29%） andβ-turn （3.39%）. Prediction of epitomes revealed that the CBP protein had 7 B cell epitopes, 7 cytotoxic T cell epitopes and 3 T helper epitopes. The information obtained from these predictions provided theoretical foundations for development of diagnostic methods and vaccines as well as preparation of monoclonal antibodies against Orf virus.