文献类型： 外文期刊

作者： Wang, Jianan ¹ ; Liu, Jun ¹ ; Zhao, Yuqiang ³ ; Sun, Minghui ¹ ; Yu, Guixu ¹ ; Fan, Jiaqin ⁴ ; Tian, Yanli ¹ ; Hu, Baishi ¹ ;

作者机构： 1.Nanjing Agr Univ, Coll Plant Protect, Key Lab Integrated Management Crop Dis & Pests, Nanjing, Peoples R China

2.Hubei Acad Agr Sci, Inst Plant Protect & Soil Fertilizer, Wuhan, Peoples R China

3.Jiangsu Prov & Chinese Acad Sci, Inst Bot, Nanjing Bot Garden Mem Sun Yat Sen, Nanjing, Peoples R China

4.Nanjing Agr Univ, Dept Plant Pathol, Lab Bacteriol, Nanjing, Peoples R China

关键词： Acidovorax citrulli; OxyR; oxidative stress; virulence traits; virulence

期刊名称：FRONTIERS IN MICROBIOLOGY （ 影响因子：6.064； 五年影响因子：6.843 ）

ISSN：

年卷期： 2022 年 13 卷

页码：

收录情况： SCI

摘要： In many bacteria, OxyR acts as a transcriptional regulator that facilitates infection via degrading hydrogen peroxide (H2O2) generated by the host defense response. Previous studies showed that OxyR also plays an important role in regulating biofilm formation, cell motility, pili relate-genes expression, and surface polysaccharide production. However, the role of OxyR has not been determined in Acidovorax citrulli strain xjl12. In the current study, the qRT-PCR and western blot assays revealed that the expression level of oxyR was significantly induced by H2O2. The oxyR deletion mutant of A. citrulli was significantly impaired bacterial tolerance to oxidative stress and reduced catalase (CAT) activity. In addition, oxyR mutant resulted in reduced swimming motility, twitching motility, biofilm formation, virulence, and bacterial growth in planta by significantly affecting flagellin and type IV pili-related gene (fliC and pilA) expression. The qRT-PCR assays and western blot revealed that OxyR positively regulated the expression of fliC and pilA. Furthermore, bacterial one-hybrid assay demonstrated that OxyR directly affected pilA and fliC promoter. Through bacterial two-hybrid assay, it was found that OxyR can directly interact with PilA and FliC. These results suggest that OxyR plays a major role in the regulating of a variety of virulence traits, and provide a foundation for future research on the global effects of OxyR in A. citrulli.