靶标发现是新农药创制最重要的基础研究，也是我国当前新农药创制研究的重要方向。青枯菌是世界范围内最重要的植物病原细菌之一，防治极其困难。申请者课题组前期工作中发现了杂环砜类化合物GU208，对青枯菌具有高效抑菌活性，但其作用靶标和作用机制并不清楚。本申请拟以GU208为基础，分别进行高活性化合物GU208修饰琼脂糖、设计合成生物素标记的GU208活性分子探针研究，通过亲和层析和生物素标记两种策略，从烟草青枯菌细胞裂解液中分离GU208的结合蛋白，进一步纯化后进行蛋白的质谱分析和蛋白结构鉴定，力求明确GU208作用靶标，为青枯菌抑制剂的新先导和新作用机制发现提供重要的科学基础。

Target identification is among the most important basic research in agrochemical innovation. It is also the important research trend of pesticide innovation in China. Ralstonia solanacearum is a kind of worldwide important plant bacterial disease and is extremely difficult to control. It was found in the preliminary study that heterocyclic sulfone compounds displayed good inhibition activity against R. solanacearum. However, the target and the mechanism of GU208 remains unknown. Thus, through modification of agarose with GU208 as well as using biotin tag to modify bioactive small molecule GU208, followed by affinity chromatography and straptevidin trap, we can isolate the binding protein of GU208 from cell lysate of R. solanacearum. Then the obtained protein sample will further be purified using SDS-PAGE. The gel will then be stained, and protein bands excised from the gel, destained and digested with trypsin, and then peptides were analyzed on mass spectrometer. Expectedly the binding protein of GU208 will be found, which will provide very important scientific basis for new lead discovery against R. solanacearum as well as new mode of action discovery.