信号分子诱导的细菌群体感应是细菌生长到一定密度时相互感应并进行基因表达调控的一种生理行为，在土壤微生物生态、土壤基因转移、有益和有害微生物功能和活性调控等方面起着重要作用。本项目选取土壤中的典型细菌菌株枯草芽孢杆菌（Bacillus subtilis）和红壤、棕壤、黑土等代表性土壤以及不同类型粘粒矿物，运用经典化学方法和红外光谱、原子力显微镜、微量热、激光共聚焦显微镜等现代分析技术，从土壤颗粒对胞外感受态信号分子CSF的化学平衡吸附、CSF与土壤颗粒结合的功能团、热效应、作用力及微观形态等方面，考察信号分子CSF与土壤颗粒结合的机制及其对枯草芽孢杆菌自然转化的影响。研究结果将丰富土壤微生物生态、土壤微生物遗传进化、土壤矿物-有机物-微生物相互作用等学科和方向的理论内容，拓宽有关研究领域，为基因工程技术在土壤环境中的安全应用提供科学依据。

Bacterial quorum sensing induced by signal molecules is a cell density dependent physiological response, which involves gene regulation. It plays essential roles in microbial ecology, gene transfer and regulation of the function and activities of beneficial and hazardous microorganisms in soil ecosystems. In this project, Bacillus subtilis, a typical soil bacterium will be employed; Red soil, Brown soil, Black soil and different clay minerals are selected. The binding mechanisms of competence and sporulation factor (CSF) molecule on soil reactive particles will be investigated by chemical equilibrium adsorption, interactive functional groups, heat effect, interaction forces and micro-morphological changes using classical chemical methods combined with modern analytical techniques including Fourier transform infrared spectroscopy, atomic force microscope, microcalorimetry and confocal laser scanning microscope. The impacts of interactions between CSF molecules and soil particles on the natural transformation of Bacillus subtilis will also be evaluated. The results obtained from this study will enrich the theories and expand the knowledges in the fields of soil microbial ecology, soil microbiological genetics and evolution, and soil mineral-organic matter-microorganism interactions. The findings will also provide scientific basis for the safe utilization of genetic engineering technology in soil environments.