产酶溶杆菌是一种重要的生防细菌。HSAF是该菌中新报道的一种结构和作用方式新颖的广谱型次生抗真菌物质。申请者已阐明该物质在产酶溶杆菌中独特的生物合成途径，但其生物合成的调控机制仍不清楚。在前期工作中，申请者以具有自主知识产权的OH11菌株为对象，从其基因组中鉴定了一个具有转录调控活性的新型孤立LuxR蛋白（LesR），发现lesR是通过一种间接机制调控HSAF生物合成的。本项目为阐明这种间接机制的遗传学基础，将利用转录组、ChIP-Seq和荧光定量等技术，鉴定位于lesR下游并调控HSAF生物合成的未知关键因子，阐明lesR对未知关键因子的调控作用，明确未知关键因子对HSAF生物合成的调控机制。研究结果将揭示一个新型的孤立LuxR蛋白调控一种新颖抗菌物质(HSAF)生物合成的作用机制，为后续遗传改良OH11获得高产HSAF生防菌株和基于HSAH设计生物农药提供理论依据和技术支撑。

Lysobacter enzymogenes is an important bacterial biocontrol agent. Recently, a secondary and broad-spectrum antifungal factor called HSAF with new chemical structure and mode of action was identifed from this bacterium. The unique biosynthetic mechanism of HSAF in this bacterium has been elucidated,however,the genetic regulatory mechanism for HSAF biosynthesis is largely unknown. On the basis of sequencing genome, a novel solo LuxR protein (LesR) with transcriptional regulatory activity was identified from strain OH11, a newly-isolated Chinese species of L. enzymogenes in our laboratory, and shown to modulate HSAF biosynthesis via an indirect and uncharacterized mechanism(s). In the present study, in order to investigate the genetic basis for this mechanism, we aim to identify the key factor(s) for modulating HSAF biosynthesis in the downstream of lesR by using transcriptomics, ChIP-Seq as well as other methods, and elucidate the mechanism(s) of lesR in the regulation of this factor(s) under genetic level. Furthermore, understanding regulatory mechanism(s) of this factor(s) in modulating HSAF biosynthesis is another objective.This knowledge is an important aid to generate genetically modified L. enzymogens strain with high-level HSAF, and further to develop HSAF-based biopesticide.