聚羟基脂肪酸酯（PHA）是近年来生物材料领域的研究热点，是微生物在生长条件不平衡时的产物，以往研究认为PHA是细菌的碳源和能量的储存物。目前已报道饥饿、紫外线辐射以及高渗透压等会诱导细菌产生PHA。新近我们首次发现芽孢杆菌天然抑菌物质C15SurfactinA诱导黄单胞菌产生大量PHA，敲除PHA合成关键基因phaC的突变菌株对C15SurfactinA敏感性显著提高，PHA可能在黄单胞菌耐药机理上起着重要作用。然而有关生物源药剂诱导病原菌产生PHA的分子机理及其生物学功能尚未清楚。本研究拟综合利用生物化学、细胞生物学、分子生物学和生物信息学等方法，解析C15SurfactinA诱导黄单胞菌产生PHA的主要代谢通路及其关键基因的功能与作用，探索C15SurfactinA诱导黄单胞菌产生的PHA代谢的机理。预期研究结果将为新的靶标药物分子设计及植物病害生物防治提供理论与应用基础。

Polyhydroxyalkanoates (PHA), which results from a polyester synthesized intracellularly imbalance in the ratio of carbon and nitrogen conditions, is a research focus in biomaterials science field. Previous studies believed that PHA was a reservoir of carbon sources and energy in microorganism. Thus far, it has been reported that the synthesis of PHA could be induced under the treatment with starvation, ultraviolet radiation or hyperosmolarity in some bacterial species. Recently, we found that C15SurfactinA, a kind of secondary metabolites from Bacillus velezensis, was able to induce the production of PHA in Xanthomonas oryzae pv.oryzae. Intriguingly, the sensitivity to C15SurfactinA of X. oryzae pv.oryzae significantly increased once the key gene phaC, which is involved in the synthesis of PHA, was knocked out. The above results imply that PHA might play certain vital roles in the mechanism of drug resistance of X. oryzae pv.oryzae. However, it is still unknown about the molecular mechanism on the synthesis of PHA and its biological significance. In this study, biochemistry, cytobiology, molecular biology and bioinformatics methods will be employed to investigate the functional roles of key genes responsible for the production of PHA induced by C15SurfactinA in X. oryzae pv.oryzae. The anticipated results will provide a scientific theoretical basis for molecular design on novel biocontrol agents, as well as our understanding on new theory and application of biocontrol of plant diseases.