水稻白叶枯病菌中一个新的糖基转移酶介导外膜蛋白糖基化调控致病性的机制研究

由水稻白叶枯病菌（Xanthomonas oryzae pv. oryzae, Xoo）引起的水稻白叶枯病是我国水稻生产上的一种重要细菌病害。在前期工作中，申请者从Xoo中鉴定到一个新的致病相关蛋白PXO_03177，初步研究表明该蛋白包含两个糖基转移酶相关的结构域，具有糖基转移酶活性；PXO_03177基因缺失显著减少了Xoo中蛋白质的糖基化水平，破坏了Xoo外膜的完整性，降低了Xoo在水稻上的致病性。本项目拟以PXO_03177为切入点，进一步明确Xoo中PXO_03177的糖基转移酶功能；鉴定受PXO_03177糖基化修饰并参与致病性调控的关键外膜蛋白；研究PXO_03177对相关外膜蛋白的糖基化修饰机制；解析PXO_03177介导外膜蛋白糖基化修饰进而调控Xoo致病性的机制。研究结果将有望揭示一种新的Xoo致病机制，为水稻白叶枯病以及其他植物细菌病害的的防控提供理论依据和新的策略。

Xanthomonas oryzae pv. oryzae (Xoo) is one of the most important bacterial pathogens that causes bacterial blight (BB) of rice in China. In the previous work in Xoo, we identified a new pathogenicity-related hypothetical protein PXO_03177, which contains two glycosyltransferase-related domains with glycosyltransferase activity. The deletion of PXO_03177 significantly impaired the pathogenicity of Xoo, damaged outer membrane integrity of Xoo and reduced the protein glycosylation levels of Xoo. Depending on the biofunction of PXO_03177, this project intends to further clarify the glycosyltransferase function of PXO_03177, identify the pathogenic-associated outer membrane proteins modified by PXO_03177-mediated glycosylation, investigate the mechanism of PXO_03177 glycosylation of outer membrane proteins and revealed the mechanism of PXO_03177-mediated outer membrane protein glycosylation in regulating Xoo pathogenicity. The results of this study will find a new pathogenic mechanism of plant-pathogenic bacteria, providing a new theoretical basis and strategy for the prevention and control of leaf blight of rice and other plant diseases.