微生物群体感应(quorum sensing，QS)理论可为研发面向实践应用的农药残留微生物降解关键技术提供理论指导。在已有工作基础上，本项目将构建枯草芽孢杆菌Bacillus subtilis BSF01高效氯氰菊酯降解酶基因ybfK突变株和新型QS感应功能突变株；应用突变株筛选以及多种分离技术鉴定QS信号分子；应用分子对接、荧光能量转移、pull-down、定点突变等技术，鉴定QS信号分子受体蛋白，研究信号通路；从基因表达、降解酶活性、降解效果3个层次探讨菌株BSF01的QS机制对降解酶基因ybfK的调控作用，基于QS机制优化菌株BSF01的应用条件。预期结果将阐明菌株BSF01降解高效氯氰菊酯的种内QS机制，理论上可填补微生物降解农药残留的QS研究空白，实践上将指导农药降解菌应用关键技术和产品研发，推动农药残留微生物降解技术的实践应用。

The theory of quorum sensing (QS) can be employed as the foundation and technical guide for the application of pesticide-degrading microorganisms. Based on the previous work, the mutants of Bacillus subtilis BSF01 will be constructed for beta cypermethrin-degrading gene ybfK and QS sensing in the present study. Coupling with multiple techniques including the isolation of effective mutants and the analysis of degradation products, the QS signal molecule will be determined. Then, the binding receptor for QS signal molecule will be identified for the further investigation of signal pathway by molecular docking, fluorescence resonance energy transfer, gene pull-down and site mutation. The regulation of gene ybfK by QS system in strain BSF01 will be discussed based on the gene transcription, degrading enzyme activity and the degradation effects. This study would reveal the QS mechanism of beta cypermethrin biodegradation specifically in strain BASF01, which would fill the gaps of QS research in pesticide-degrading bacteria and facilitates the practical application of the microbial remediation of pesticide residues as a key technique guidance.