论文部分内容阅读
通过对Xcc 8004菌株的hrp基因进行逐一敲除,系统研究单个hrp基因对Xcc致病性的贡献。结果表明,9个hrc(hypersensitive response and conserved)基因单独突变后在满身红萝卜上的致病性和在辣椒ECW-10R上激发HR的能力完全丧失;9个hrp基因中,hrpW突变后在辣椒ECW-10R上仍能产生HR,满身红萝卜上致病性减弱,其余hrp基因突变后致病性和过敏反应均丧失;4个hpa(hrp associated protein)基因突变后,hpaA和hpaB突变体完全丧失在满身红萝卜上的毒性也不能在辣椒ECW-10R上引起HR,hpa1和hpaP突变后致病性和HR显著减弱。另外,通过RT-PCR对Xcc 8004 hrp基因簇的每个基因受hrpX和hrpG的调控情况进行分析,结果表明所有hrp基因在不同程度上都受到hrpG、hrpX的正向调控。
By knocking out the hrp gene of Xcc 8004 strain one by one, the contribution of a single hrp gene to the pathogenicity of Xcc was systematically investigated. The results showed that the pathogenicity of 9 hrc hypersensitive response and conserved genes was completely lost in carrot and the ability of HR stimulated by pepper ECW-10R was completely lost. Among 9 hrp genes, hrpW was mutated in Pepper ECW-10R still produce HR, the pathogenicity of carrot covered weakened, the rest of the hrp gene mutation and pathogenicity and allergic reactions are lost; hpa (hrpA) and hpaB mutations Complete loss of body weight on carrots also failed to cause HR, chilli ECW-10R mutations, hpa1 and hpaP mutations after pathogenicity and HR significantly weakened. In addition, the regulation of hrpX and hrpG on each gene of Xcc 8004 hrp gene cluster by RT-PCR showed that all hrp genes were positively regulated by hrpG and hrpX to varying degrees.