群体感应TraI/R系统调控Pseudomonas baetica Mr36风化矿物的分子机制

硅酸盐矿物与微生物相互作用对矿物风化、土壤形成和全球气候变化产生深远的影响，而群体感应系统能够调控细菌多种生理功能以适应环境的变化。本项目以具有群体感应TraI/R系统的高效矿物风化细菌Pseudomonas baetica Mr36为供试菌株，以钾长石和黑云母为供试矿物，采用基因敲除技术结合现代仪器分析手段，研究Mr36野生株、TraI/R基因缺失突变株和回补株对矿物的风化效能，矿物对菌株生长、代谢及其在矿物表面分布和活性的影响；采用转录组学、蛋白质组学和基因敲除技术结合生物信息学分析手段重点分析Mr36菌株中受TraI/R系统调控的与矿物风化相关的基因和蛋白及其调控机制，并进一步验证Mr36菌株中与矿物风化相关基因的功能。预期研究结果不仅可以为群体感应系统调控细菌风化硅酸盐矿物的分子机制提供实验依据，而且可以为高效矿物风化细菌的利用提供菌种资源。

The interactions between silicate minerals and microbes play profound influences on rock weathering, soil formation, and global climate changes and quorum sensing system controls various functions of bacteria for adapting to the changes in the environments. In this study, one highly efficient mineral-weathering bacterium Pseudomonas baetica Mr36 with quorum sensing traI/R system and two silicate minerals (feldspar and biotite) are used as the tested bacterium and minerals. The effect of the wild type strain Mr36, its mutants (Mr36∆traI, Mr36∆traR, and Mr36∆traI∆traR), and complemented strains on the mineral weathering and the effects of the minerals on the bacterial growth, metabolism, and distribution on the mineral surfaces of these strains are investigated by gene knockout and modern instrument analyses. The mineral weathering-related genes and proteins regulated by the traI/traR system of strain Mr36 and the regulatory mechanisms involved are analyzed through the comparative transcriptome and proteomic analyses and the gene knockout as well as the bioinformatics analysis. The functions of the mineral weathering-related genes are further verified by the gene knockout, qRT-PCR, and gene heterologous expression. The expected results will not only provide the experimental basis for improved insight into the interactions between bacteria and minerals and the molecular mechanisms involved in mineral weathering regulated by bacterial quorum sensing system but also provide the bacterial resources for the utilization of the efficient mineral-weathering bacteria.