副猪嗜血杆菌丝氨酸蛋白酶基因的克隆及生物信息学分析

为研究副猪嗜血杆菌(Haemophilus parasuis,Hps)丝氨酸蛋白酶(espP)作为疫苗候选抗原的可能性,根据GenBank中Hps espP基因(登录号:HAPS_1381)设计引物,以Hps血清11型(H456)菌株的DNA为模板,PCR扩增目的基因并测序。将该基因核苷酸序列翻译成氨基酸序列后,对Hps espP蛋白的信号肽、亲水性区域和B细胞抗原表位进行预测,并预测了该蛋白C端的3D结构。结果显示,Hps espP基因序列全长2 343 bp,共可编码781个氨基酸,其中氨基酸序列的1—23位预测为信号肽。Hps espP蛋白含有12个亲水性区域,并预测含有12个B淋巴细胞抗原表位。构建Hps espP蛋白3D结构显示,该蛋白C端是由12个β折叠层围成的桶状结构。本试验为进一步研制新型副猪嗜血杆菌Hps espP蛋白多肽疫苗奠定基础。

Cloning and Bioinformatics Analysis of espP Gene of Haemophilus parasuis

In order to evaluate whether Haemophilus parasuis espP gene could use as a vaccine candidate antigen or not,the espP gene was amplified by PCR using the specific primers that designed according to corresponding sequence getting form GenBank (accession No.:HAPS_1381) and then sent to sequence.After translating the DNA sequence into amino acid sequence,the signal peptide,hydrophilic region,linear B cell epitopes and 3D structure of Hps espP protein were predicted using multiple bioinformatics analysis.The results showed that the full length of Hps espP gene was 2 343 bp,encoding 781 aa.The first 23 aa were predicted as signal peptide.There were 12 hydrophilic regions and 12 B cell epitopes in the Hps espP protein.The 3D structure of C-terminal of the protein was consisted of a monomeric β-barrel containing 12 β-strands and a central pore.The study laid the foundation for further development of molecular vaccines based on espP protein against Hps infection.