中文摘要：

目的确认RTX家族胞外蛋白A（RTX family exoprotein A,RfeA）为2-型猪链球菌（Streptococcus suis serotype 2,SS2）的分泌蛋白。方法通过生物信息学软件分析RfeA的氨基酸序列,预测RfeA在SS2中的分布;以纯化的RfeA重组蛋白为免疫原免疫小鼠,制备RfeA鼠多抗血清,间接ELISA检测抗血清效价;以制备的RfeA抗血清为一抗,利用ELISA方法分析RfeA在05ZYH33株培养上清中的分布,通过实验证实生物信息学预测的结果。结果生物信息学软件分析RfeA氨基酸序列,预测RfeA为SS2分泌性蛋白;ELISA方法分析发现RfeA存在于05ZYH33株培养上清中,是SS2分泌性蛋白。结论实验研究结果与生物信息学预测一致,RfeA为SS2分泌性蛋白的确定为进一步研究RfeA的功能以及在SS2致病过程中扮演的角色奠定了基础。

英文摘要：

The aim of this study is to verify RTX family exoprotein A（RfeA） secreted into supernatant by Streptococcus suis serotype 2（S.suis 2） strain 05ZYH33.Bioinformatics softwares were used to analyze the amino acid sequence of RfeA,and then distribution of RfeA in S.suis 2 was predicted.Antiserum against RfeA was prepared by immunizing mice with purified recombinant RfeA;antiserum titer was detected by indirect ELISA.In addition,ELISA was also applied to confirm the predicted result of bioinformatics softwares.Bioinformatics analysis indicated that RfeA is a secreted protein,and ELISA demonstrated that RfeA was secreted into supernatant by strain 05ZYH33.The identification of RfeA as a secreted protein by S.suis 2 would lay foundation for further research on the function of RfeA and the role of RfeA in infection caused by S.suis 2.