2-型猪链球菌保护性抗原ESA的细胞定位及B细胞表位预测

摘要

The cellular location and B cell epitopes of the protective antigen ESA (epidermal surface antigen, ESA) ofStreptococcus suis serotype 2 (S. suis 2) were predicted for the development of a multi-epitope vaccine using bioinformatics. Putative amino sequence of ESA was analyzed using bioinformatics software containing signal peptide and transmembrane region prediction. The secondary structural fl exible regions of ESA were analyzed by using the Garnier-Robson’s method, Chou-Fasman’s method and Karplus-Schulz’s method based on its putative amino sequence. The hydrophilicity plot, surface probability plot and antigenicity index were obtained by using the methods of Kyte-Doolittle, Emini and Jameson-Wolf, respectively. Combined with these results, ESA was predicted as a transmembrane protein and amino acids 30~35, 59~64, 178~185, 245~253 at the N-terminus might represent possible B cell epitopes for ESA. In conclusion, the cellular localization and B cell epitopes of ESA were predicted based on multiple parameters and softwares, which would benefi t design and future research of a multi-epitope vaccine.%通过生物信息学方法预测2-型猪链球菌（Streptococcus suis serotype 2，SS2）保护性抗原ESA（epidermal surface antigen, ESA）在SS2中的分布和B细胞表位，为研究SS2的多表位疫苗奠定基础。以ESA推定的氨基酸序列为基础，通过生物信息学软件对ESA进行信号肽、跨膜序列等分析，然后分别以Kyte-Doolittle法、Emini法和Jameson-Wolf法分析蛋白的亲水性、表面可能性以及抗原指数；辅以Garnier-Robson法、Chou-Fasman法和Karplus-Schulz法分析蛋白二级结构中柔性区域，进而预测ESA的B细胞表位。结果表明，ESA为跨膜蛋白，B细胞表位位于N-端第30~35、59~64、178~185、245~253区域。多参数或多个软件联合使用能预测SS2保护性抗原ESA的B细胞表位和细胞定位，为实验研究提供帮助，大大缩减实验时间。