Paenibacillus polymyxa SQR-21中杀镰孢菌素合成基因簇启动子分析与转录调控研究

项目名称： Paenibacillus polymyxa SQR-21中杀镰孢菌素合成基因簇启动子分析与转录调控研究

项目编号： No.31301845

项目类型： 青年科学基金项目

立项/批准年度： 2014

项目学科： 农业科学

项目作者： 张楠

作者单位： 南京农业大学

项目金额： 23万元

中文摘要： 合理施用根际有益菌是克服作物土传病害、减少我国农用化学品施用的有效途径之一。多粘类芽孢杆菌（Paenibacillus polymyxa）是一类重要的根际有益菌，其产生的抗生素类次生代谢物质fusaricidin是拮抗病原真菌的主要活性成分，但有关其功能基因启动子分析与转录调控的研究还鲜有报道。本申请以实验室分离保存并已推广应用的根际有益菌P. polymyxa SQR-21为材料，确定其编码fusaricidin合成酶的fus基因簇的转录起始位点，研究其不同长度启动子在大肠杆菌和SQR-21中的转录强度。筛选SQR-21的胞内蛋白中能与该启动子区域结合的转录调控因子并验证其功能，最后通过过表达/敲除这些正/负调控因子以提高SQR-21产生fusaricidin和拮抗病原真菌的能力。本研究将为进一步增强SQR-21产生拮抗物质能力的工作提供理论依据和技术支持。

中文关键词： 多粘类芽孢杆菌；杀镰孢菌素；fus基因簇；启动子结构；转录调控

英文摘要： Application of rhizosphere beneficial microbes in stimulation of plant growth and biocontrol of soil-borne diseases is an important strategy for suppression of soil-borne disease and decrease the input of agricultural chemicals. Paenibacillus polymyxa, an important PGPR group, could produce fusaricidins, which is the major component contributing to suppression of fungal pathogens. However, few research has focused on the transcription and regulation imformation of fus gene cluster that responsible for synthesis of fusaricidin. P. polymyxa SQR-21 was isolated by our laboratory and has been widely applied in agricultural production. In this project, the transcriptional start site of fus gene cluster, which encoding the fusaricidin synthetase, will be determined. The transcriptional activity of the promoters with different length in Escherichia coli and SQR-21 will be evaluated. The potential transcription factor that could bind to the promoter region of fus gene cluster will be screened from the intracellular protein of SQR-21 and confirmed for their binding function. Finnally, studies for improvement of the ability of SQR-21 to secret fusaricidin and suppress fungal pathogen by overexpression/knock out of these confirmed positive/nagative regulators will be carried out. This research will provide theoretical inst

英文关键词： Paenibacillus polymyxa；fusaricidin；fus cluster；promoter structure；transcriptional regulation