Bacterial panicle blight caused by Burkholderia glumae is one of the most severe seed-borne bacterial diseases of rice in the world. Currently, this disease has affected many countries of Asia, Africa, South and North...Bacterial panicle blight caused by Burkholderia glumae is one of the most severe seed-borne bacterial diseases of rice in the world. Currently, this disease has affected many countries of Asia, Africa, South and North America. It is a typical example of the shifting from minor plant disease to major disease due to the changes of environmental conditions. Some virulent factors of B. glumae have been identified, including toxoflavins and lipases, whose productions are dependent on the Tof I/Tof R quorum-sensing system, and type III effectors. In spite of its economic significance, neither effective control measure for this disease nor resistant rice variety is currently available. In recent years, genomics, transcriptomics and other molecular methods have provided useful information for better understanding the molecular mechanisms underlying B. glumae virulence and the rice defence mechanisms against pathogens. For the prevention of this pathogen, our laboratory has developed a rapid and sensitive multiplex PCR assay for detecting and distinguishing B. glumae from other Burkholderia species. This improved understanding of B. glumae will shed new light on bacterial panicle blight disease management.展开更多
Horizontal gene transfer(HGT)has been proved a major driving force in prokaryotic evolution.However,the molecular functions of these transferred genes in pathogenic bacteria especially plant pathogenic bacteria are st...Horizontal gene transfer(HGT)has been proved a major driving force in prokaryotic evolution.However,the molecular functions of these transferred genes in pathogenic bacteria especially plant pathogenic bacteria are still not fully investigated.In this study,the whole-genome in silico analysis was performed and found a syringopeptin synthetase(syp)homolog in Burkholderia glumae,which can cause bacterial panicle blight in rice,was predicted to be horizontally transferred from Pseudomonas ancestor with solid confidence by phylogenetic analysis.The comprehensive molecular experiments were performed to study the potential role of this gene in B.glumae.Inoculation of rice panicles with the syp mutant resulted in 60%lower disease index compared with the wild type(WT)parent strain,suggesting the requirement of syp for the full virulence of B.glumae.Chromatography analysis of exudates from B.glumae showed suppression of synthesis of metabolites analogous to syringopeptin in the mutants.All these data raise the possibility of HGT phenomenon in shaping the virulence and adaptation of B.glumae over evolutionary time.展开更多
目的探讨大动脉炎的超声造影特点及在判断病变活动性中的价值。方法选取2014年10月至2016年2月在解放军总医院诊断为大动脉炎患者23例,共50处病变区域,分为活动期组与非活动期组,采用超声造影进行定性和定量分析,比较活动期组超声造影...目的探讨大动脉炎的超声造影特点及在判断病变活动性中的价值。方法选取2014年10月至2016年2月在解放军总医院诊断为大动脉炎患者23例,共50处病变区域,分为活动期组与非活动期组,采用超声造影进行定性和定量分析,比较活动期组超声造影情况与非活动期组的差异以及与临床活动性判断的比较。结果活动期组与非活动期组造影情况(增厚管壁明显增强与少量增强、无增强的构成)的比较,差异有统计学意义(χ2=39.23,P<0.01);同时二者管腔增强强度[(6.67±2.80)d B vs(5.62±1.72)d B]比较,差异无统计学意义(t=1.51,P>0.05);活动期组的增厚管壁增强强度高于非活动期组[(3.07±2.17)d B vs(0.07±0.08)d B],差异有统计学意义(t=8.71,P<0.01);以增厚管壁造影剂明显增强作为判断活动性的标准,准确性60%,敏感度50%,特异度100%,说明100%的非活动性病变的增厚管壁造影剂无明显增强;若以增厚管壁造影剂无增强作为判断非活动性的标准,则准确性96%,敏感度95%,特异度100%,说明95%的活动性病变的增厚管壁造影剂有增强。结论超声造影在判断大动脉炎的活动性上有指导意义,增厚管壁造影剂有无增强可作为判断大动脉炎活动性的指标。展开更多
基金supported by the Special Fund for Agro-Scientific Research in the Public Interest of China(Grant No.201303015)the National Natural Science Foundation of China(Grant No.30871655)
文摘Bacterial panicle blight caused by Burkholderia glumae is one of the most severe seed-borne bacterial diseases of rice in the world. Currently, this disease has affected many countries of Asia, Africa, South and North America. It is a typical example of the shifting from minor plant disease to major disease due to the changes of environmental conditions. Some virulent factors of B. glumae have been identified, including toxoflavins and lipases, whose productions are dependent on the Tof I/Tof R quorum-sensing system, and type III effectors. In spite of its economic significance, neither effective control measure for this disease nor resistant rice variety is currently available. In recent years, genomics, transcriptomics and other molecular methods have provided useful information for better understanding the molecular mechanisms underlying B. glumae virulence and the rice defence mechanisms against pathogens. For the prevention of this pathogen, our laboratory has developed a rapid and sensitive multiplex PCR assay for detecting and distinguishing B. glumae from other Burkholderia species. This improved understanding of B. glumae will shed new light on bacterial panicle blight disease management.
基金the National Key R&D Program of China(2018YFD0201202 and 2017YFD0201108)the Agri-X Interdisciplinary Fund of Shanghai Jiao Tong University,China(Agri-X2017010)+3 种基金the State Key Laboratory for Biology of Plant Diseases and Insect Pests of Shanghai Jiao Tong University(SKLOF201802)the Shanghai Committee of Science and Technology(19390743300)the National Natural Science Foundation of China(31200003 and 31770772)Joint Research Funds for Translational Medicine at Shanghai Jiao Tong University(ZH2018ZDA06).
文摘Horizontal gene transfer(HGT)has been proved a major driving force in prokaryotic evolution.However,the molecular functions of these transferred genes in pathogenic bacteria especially plant pathogenic bacteria are still not fully investigated.In this study,the whole-genome in silico analysis was performed and found a syringopeptin synthetase(syp)homolog in Burkholderia glumae,which can cause bacterial panicle blight in rice,was predicted to be horizontally transferred from Pseudomonas ancestor with solid confidence by phylogenetic analysis.The comprehensive molecular experiments were performed to study the potential role of this gene in B.glumae.Inoculation of rice panicles with the syp mutant resulted in 60%lower disease index compared with the wild type(WT)parent strain,suggesting the requirement of syp for the full virulence of B.glumae.Chromatography analysis of exudates from B.glumae showed suppression of synthesis of metabolites analogous to syringopeptin in the mutants.All these data raise the possibility of HGT phenomenon in shaping the virulence and adaptation of B.glumae over evolutionary time.
文摘目的探讨大动脉炎的超声造影特点及在判断病变活动性中的价值。方法选取2014年10月至2016年2月在解放军总医院诊断为大动脉炎患者23例,共50处病变区域,分为活动期组与非活动期组,采用超声造影进行定性和定量分析,比较活动期组超声造影情况与非活动期组的差异以及与临床活动性判断的比较。结果活动期组与非活动期组造影情况(增厚管壁明显增强与少量增强、无增强的构成)的比较,差异有统计学意义(χ2=39.23,P<0.01);同时二者管腔增强强度[(6.67±2.80)d B vs(5.62±1.72)d B]比较,差异无统计学意义(t=1.51,P>0.05);活动期组的增厚管壁增强强度高于非活动期组[(3.07±2.17)d B vs(0.07±0.08)d B],差异有统计学意义(t=8.71,P<0.01);以增厚管壁造影剂明显增强作为判断活动性的标准,准确性60%,敏感度50%,特异度100%,说明100%的非活动性病变的增厚管壁造影剂无明显增强;若以增厚管壁造影剂无增强作为判断非活动性的标准,则准确性96%,敏感度95%,特异度100%,说明95%的活动性病变的增厚管壁造影剂有增强。结论超声造影在判断大动脉炎的活动性上有指导意义,增厚管壁造影剂有无增强可作为判断大动脉炎活动性的指标。
