中文摘要：

分析沙眼衣原体多形态膜蛋白D（PmpD）的基因序列并预测PmpD蛋白的B细胞抗原表位。在GenBank中检索沙眼衣原体不同血清型的PmpD基因序列，进行序列比对分析。以L2血清型PmpD基因序列为材料，采用Karplus-Schulz、Chou-Faaman和Gamier-Robson方案预测蛋白质的二级结构和柔性区；按Jamesonv-wolf方案预测抗原指数，运用Kyte-Doolittle方案预测PmpD氨基酸的亲水性，利用Emini方案预测蛋白质的表面可及性。检索到20个沙眼衣原体不同菌株的PmpD基因序列，分析发现其核苷酸序列非常保守，一致性高达99．14％-100％；对预测结果综合分析，推测最有可能的B细胞表位位于PmpDN端的67-74、132-140、335-340、851-861、972-988及1091-1097。多参数方案综合预测PmpD蛋白的B细胞抗原表位，为进一步实验鉴定PmpD抗原表位及其多表位疫苗设计和研究奠定基础。

英文摘要：

To analyze gene sequence and predict the B cell epitopesof Chlamydia trachomatis （Ct） polymorphic membrane protein D（PmpD）. Search the gene sequences of the different Ct serotypes in GenBank, and then align them by Laser-Gene software. The secondary structure and the flexibility plot of PmpD of Ct serovar L2 were predicted by the algorithm of Karplus-Sehulz, Chou-Fasman and Gamier-Robson based on PmpD sequence, and the antigenic index ,the hydrophilieity plot and the surface probability plot were predicted by the methods of Jamesonv-Wolf, Kyte-Doolittle and Emini respectively. Sequence alignments indicate that the PmpD genes of the 20 different Ct strains share 99.14-100% identical nucleotide sequences. The B cell epitopes of PmpD by these predicted results was analyzed, which are most likely localized in or adjacent to its N-terminal No. 67-74,132-140,335-340,851-861,972-988,1091-1097 of PmpD. The results obtained by epitopes prediction using multiple parameters are helpful for further epitopes identification and design of multiepitopes-based vaccine of PmpD.