论文部分内容阅读
【目的】前期研究中从Tn5转座子插入的水稻条斑病菌突变体库中获得了17个胞外多糖改变的突变体。【方法】本文对这些突变体的Tn5插入位点和基因类型进行了鉴定。【结果】结果显示,胞外多糖减少的11个突变体中多数为Tn5插入在已知的gum、xan和wxoc基因簇上,Xoryp_4217、Xoryp_2488和Xoryp_0918为未知的与胞外多糖产生有关的基因,属首次报道;6个胞外多糖增多的突变体中,fimO、pilY和xopQ与胞外多糖产生有关,但在水稻条斑病菌中未见报道;Xoryp2392、Xoryp_4221和Xoryp_3511为首次鉴定,其中Xoryp_3511仅在水稻黄单胞菌中存在。毒性测定结果显示,胞外多糖减少的突变体在水稻上的毒性变弱,而胞外多糖增加的突变体在水稻上的毒性没有显著变化。【结论】这些结果为进一步分析水稻条斑病菌胞外多糖代谢途径以及与水稻的互作关系奠定了基础。
【Objective】 In the previous study, 17 mutants with extracellular polysaccharides were obtained from the mutant library of S. variabilis inserted by Tn5 transposon. 【Method】 The Tn5 insertion sites and genotypes of these mutants were identified. 【Result】 The results showed that the majority of the 11 mutants with reduced extracellular polysaccharide were Tn5 inserted into the known gum, xan and wxoc gene clusters. Xoryp_4217, Xoryp_2488 and Xoryp_0918 were unknown genes related to extracellular polysaccharide production, Among the six extracellular polysaccharides, fimO, pilY and xopQ were related to the production of extracellular polysaccharides, but not found in X. fragariae. Xoryp2392, Xoryp_4221 and Xoryp_3511 were the first to be identified, of which Xoryp_3511 In X. hygromyces exists. Toxicity assay results showed that mutants with decreased exopolysaccharides weakened in rice, while the mutants with increased exopolysaccharides showed no significant changes in rice toxicity. 【Conclusion】 These results provide the basis for further analysis of the metabolic pathway of the extracellular polysaccharide of rice leaf spot pathogens and its interaction with rice.