重要人兽共患病原猪链球菌酪氨酸激酶/磷酸酶组分Cps2B/C/D对荚膜合成及毒力的分子调控机制研究

2型猪链球菌(S.suis2)是一种重要的人兽共患病病原，感染人、畜可导致多种疾病且病死率极高，而其高致病性的分子机制尚不清楚。课题组前期发现酪氨酸磷酸化信号组分对CPS合成具有重要影响，为深入探明其调控机制，本研究拟在构建cps2B、cps2C、cps2D基因突变株和原核表达活性蛋白的基础上；利用体内、体外实验明确Cps2B/C/D三者之间的磷酸化与去磷酸化调控关系，利用质谱技术鉴定其关键磷酸化氨基酸位点。将RNA-seq转录组与iTRAQ蛋白组技术结合，筛选Cps2B、Cps2C、Cps2D调控的靶基因及靶底物蛋白，尤其是Cps2B/C/D与cps基因编码蛋白之间的磷酸化调控关系。本研究是对病原链球菌酪氨酸磷酸化信号机制的重要补充，将揭示Cps2B/C/D对细菌荚膜合成调控的分子机制，为S.suis特异性防治新药研发提供新思路和理论参考。

Streptococcus suis type 2 (s. suis 2) is an important zoonotic pathogen. Human and animal infections can cause a variety of diseases with a high fatality rate, and the molecular mechanism of its high pathogenicity is still unknown.The research group found that tyrosine phosphorylation signal components have an important influence on CPS synthesis. In order to explore its regulatory mechanism, this study intends to construct cps2B, cps2C and cps2D gene mutant strains.The phosphorylated kinases and phosphorylases activities of the recombinant proteins Cps2B, Cps2C and Cps2D were detected in vitro, the regulatory relationship between phosphorylation and dephosphorylation of Cps2B/C/D was identified, and the key phosphorylated amino acid sites were identified by mass spectrometry.The RNA-seq transcriptome was combined with iTRAQ proteome technology to screen Cps2B, Cps2C and Cps2D regulated target genes and target substrate proteins, especially the phosphorylation regulatory relationship between Cps2B/C/D and CPS gene coding proteins.This study is an important supplement to the tyrosine phosphorylation signaling mechanism of pathogenic streptococcus, and reveals the molecular mechanism of Cps2B/C/D in the regulation of bacterial capsular synthesis.It provides new ideas and theoretical references for S. suis specific prevention and treatment drug research and development.