Site-specific insertion plasmid pVO155 was used to knockout the genes involved in the alternation of host range of strain Bradyrhizobium diazoefficiens USDA 110 from its original determinate-nodule-forming host soybean (Glycine max), to promiscuous and indeterminate-nodule-forming shrubby legume sophora (Sophora flavescens). Symbiotic phenotypes of these mutants inoculated to these two legumes, were compared to those infected by wild-type strain USDA 110. Six genes of the total fourteen Tn5 transposon mutated genes were broken using the pVO155 plasmid. Both Tn5 and pVO155-inserted mutants could nodulate S. flavescens with different morphologies of low-efficient indeterminate nodules. One to several rod or irregular bacteroids, containing different contents of poly-β-hydroxybutyrate or polyphosphate were found within the symbiosomes in nodulated cells of S. flavescens infected by the pVO155-inserted mutants. Moreover, none of bacteroids were observed in the pseudonodules of S. flavescens, infected by wild-type strain USDA 110. These mutants had the nodulation ability with soybean but the symbiotic efficiency reduced to diverse extents. These findings enlighten the complicated interactions between rhizobia and legumes, i. e., mutation of genes involved in metabolic pathways, transporters, chemotaxis and mobility could alter the rhizobial entry and development of the bacteroid inside the nodules of a new host legume.

使用位点特异性插入质粒pVO155来敲除重氮根瘤菌缓释假单胞菌USDA 110宿主范围从其原始确定结节形成宿主大豆（Glycine max）到杂乱和不确定结节形成的矮豆科植物的基因。槐（Sophora flavescens）。将这两个豆科植物接种的这些突变体的共生表型与野生型USDA 110感染的突变体进行了比较。使用pVO155质粒破坏了总共14个Tn 5转座子突变基因中的6个基因。Tn 5和pVO155插入的突变体都可以根瘤黄萎病菌。具有低效率不确定结节形态的不同形态。一个至几个棒状或不规则类菌体，包含聚β羟基丁酸酯或聚磷酸盐的不同内容物在形成根瘤的细胞内symbiosomes发现苦参由pVO155插入突变体感染。此外，在黄萎链霉菌的假结节中未观察到任何类细菌。，被野生型USDA 110感染。这些突变体具有与大豆的结瘤能力，但共生效率在不同程度上降低。这些发现启发了根瘤菌和豆科植物之间复杂的相互作用，即，与代谢途径，转运蛋白，趋化性和移动性有关的基因突变可能会改变新宿主豆科植物瘤内根瘤菌的进入和发育。