木霉菌抗真菌物质Harzianic Acid的合成机制及其应用研究

在前期通过基因敲除确定木霉菌NJAU 472中聚酮类Harzianolide的合成基因簇过程中，获得一株异常插入突变子NJAU 5688，分泌大量的黄色物质，表现出对多种植物病原真菌更强的拮抗能力。通过代谢组和核磁共振确定NJAU 5688中积累的黄色物质物质是Harzianic Acid；结合转录组数据分析和基因敲除，初步确定Harzianic Acid的合成基因簇。本项目将完全解析Harzianic Acid合成机制，为提高工程菌株合成Harzianic Acid水平和工业化大规模发酵Harzianic Acid奠定基础。其次，解析Harzianic Acid抑制真菌机制，为Harzianic Acid的应用阐明理论基础；再次，分析施用Harzianic Acid对植物根际微生物群落结构变化，研究其对尖孢镰刀菌侵染植物根系的影响，并结合木霉菌强化构建抑制尖孢镰刀菌生长的微生物群落结构。

In the previous research, an abnormal mutant NJAU 5688, which secreted a large amount of yellow pigment and showed stronger antagonism against a variety of plant pathogenic fungi was obtained in verifying the synthetic gene cluster of harzianolide by gene knockout, The molecular weight of the accumulated compound was determined by metabolomics. The structure of Harzianic acid was determined by nuclear magnetic resonance in extracts of NJAU 5688. With transcriptomic and gene deleting, the biosynthesis cluster of Harzianic Acid was preliminarily fixed. This project will completely explore the biosynthesis mechanism of Harzianic Acid, in order to improve the production of Harzianic acid in engineering strain and work for industrialized large-scale fermentation of Harzianic acid. Secondly, analyzing antifungal mechanism of Harzianic acid against pathogenic fungi will provide scientific reference for the application. Thirdly, plant rhizosphere microbial community and structure will be investigated, supplemented with Harzianic acid. We will study the effect of Harzianic acid on Fusarium oxysporum infecting plant roots, for establishing microbial community that inhibites the growth of Fusarium oxysporum.