抗生素Bacillomycin D调控芽孢杆菌根表生物膜形成的分子机理

项目名称： 抗生素Bacillomycin D调控芽孢杆菌根表生物膜形成的分子机理

项目编号： No.31501833

项目类型： 青年科学基金项目

立项/批准年度： 2016

项目学科： 植物保护学、园艺学与植物营养学

项目作者： 徐志辉

作者单位： 南京农业大学

项目金额： 21万元

中文摘要： 根际有益微生物在抵御土传病害方面发挥重要作用，充分利用根际有益微生物资源是减少农用化学品投入、发展可持续农业的重要途径之一。解淀粉芽孢杆菌是一类重要的根际有益菌，其分泌的抗生素类物质Bacillomycin D是拮抗病原真菌的主要活性成分，但有关它对芽孢杆菌生物膜形成的调控研究还鲜有报道。本申请以实验室分离保存并已推广应用的根际有益菌解淀粉芽孢杆菌SQR9为实验材料，首先确定Bacillomycin D突变体生物膜形成过程中差异表达的基因，然后通过基因敲除明确其中与生物膜形成相关的关键基因（正/负调控因子），并筛选能和Bacillomycin D绑定的受体蛋白并验证其功能，阐明Bacillomycin D调控SQR9生物膜形成的分子机制。最后通过过表达/敲除这些正/负调控因子以增强SQR9在黄瓜根际的定殖能力。本研究将为进一步增强SQR9的农业应用效果提供理论依据和技术支持。

中文关键词： 根际；解淀粉芽孢杆菌；根际定殖；调控机理；抗生素

英文摘要： Plant growth-promoting rhizobacteria (PGPR) play important roles in biocontrol of soil-borne diseases, therefore application of PGPR is an important strategy for reducing the input of agricultural chemicals and supporting the sustainability of agriculture. Bacillus amyloliquefaciens, an important PGPR group, could produce Bacillomycin D which is the major component contributing to suppression of fungal pathogens. However, few research has focused on the molecular mechanisms of how Bacillomycin D involved in the biofilm formation of Bacillus. B.amyloliquefacien SQR9 was isolated by our lab and applied widely in agricultural practice. In this project, differentially expressed genes between SQR9 and SQR9M1 (bmyD-disrupted mutant),which were involved in the biofilm formation, will be determined by transcriptome analysis. Then, the key regulator (positive or negative) will be detected by gene knockout. Finally, studies for enhancing the rhizosphere colonization of SQR9 on cucumber root will be worked out by overexpression /knockout of these confirmed positive/negative regulators. This research will provide theoretical instructions and technical support for improving the agricultural application of B. amyloliquefacien SQR9.

英文关键词： rhizosphere;Bacillus amyloliquefaciens ;rhizosphere colonization;regulation mechanism;antibiotic