金黄色葡萄球菌疫苗候选分子SirH的B细胞抗原表位预测

Prediction of B cell antigenic epitope for vaccine candidate SirH against Staphylococcus aureus

预测金葡菌疫苗候选分子SirH的B细胞抗原表位。用PCR方法从金葡菌临床分离株的基因组DNA中扩增出sirH基因,插入表达载体pET-28a(+)中,构建重组表达载体pET28a-sirH,双酶切鉴定并测序,通过与GenBank中登录的金葡菌sirH基因序列的比对,获得此临床分离株sirH的核苷酸序列和推导的氨基酸序列。在此基础上,应用生物信息学软件分析SirH蛋白的二级结构柔性区域、亲水性、表面可能性和抗原指数等参数。综合各参数预测结果,SirH蛋白N-端第49-57、62-75、83-123、128-162、194-208、242-252、334-350、401-415、452-543、550-564、573-622区段很有可能存在B细胞抗原表位。SirH蛋白B细胞抗原表位的预测,为后续表达SirH主要抗原表位和研究其免疫保护作用奠定了基础。

B cell antigenic epitope for vaccine candidate SirH against Staphylococcus aureus was predicted. The sirH gene was amplified from genomic DNA of Staphylococcus aureus clinical strain by PCR. The gene fragment was inserted into the expression vector pET 28a（ ＋ ）to build pET28a sirH. The recombinant plasmid was identified by restriction analysis and sequencing. The nucleotide and deduced amino acid sequences of sirH gene were compared with those of Staphylococcus aureus available from the GenBank database, based on which the secondary structure of flexible region, hydrophilicity, surface probability and antigenicity index for SirH protein were analyzed by bioinformatics software. Combined with these results, the N terminal No. 49 57,62 75,83 123,128-162,194-208, 242 252,334 350,401-415,452 543,550-564,573-622 were be the possible B cell antigenic epitopes for SirH. B cell antigenic epitope for SirH against Staphylococcus aureus was predicted,which would lay foundation on expression and evaluation of the major antigen epitope for immune efficacy.