Tsyganov Viktor E, Tsyganova Anna V, Gorshkov Artemii P, Seliverstova Elena V, Kim Viktoria E, Chizhevskaya Elena P, Belimov Andrey A, Serova Tatiana A, Ivanova Kira A, Kulaeva Olga A, Kusakin Pyotr G, Kitaeva Anna B, Tikhonovich Igor A
All-Russian Research Institute for Agricultural Microbiology, Saint Petersburg, Russia.
Saint Petersburg Scientific Center (RAS), Saint Petersburg, Russia.
Front Microbiol. 2020 Jan 29;11:15. doi: 10.3389/fmicb.2020.00015. eCollection 2020.
Two transgenic strains of bv. , 3841-PsMT1 and 3841-PsMT2, were obtained. These strains contain the genetic constructions and coding for two pea ( L.) metallothionein genes, and , fused with the promoter region of the gene. The ability of both transgenic strains to form nodules on roots of the pea wild-type SGE and the mutant SGECd, which is characterized by increased tolerance to and accumulation of cadmium (Cd) in plants, was analyzed. Without Cd treatment, the wild type and mutant SGECd inoculated with strains 3841, 3841-PsMT1, or 3841-PsMT2 were similar histologically and in their ultrastructural organization of nodules. Nodules of wild-type SGE inoculated with strain 3841 and exposed to 0.5 μM CdCl were characterized by an enlarged senescence zone. It was in stark contrast to Cd-treated nodules of the mutant SGECd that maintained their proper organization. Cadmium treatment of either wild-type SGE or mutant SGECd did not cause significant alterations in histological organization of nodules formed by strains 3841-PsMT1 and 3841-PsMT2. Although some abnormalities were observed at the ultrastructural level, they were less pronounced in the nodules of strain 3841-PsMT1 than in those formed by 3841-PsMT2. Both transgenic strains also differed in their effects on pea plant growth and the Cd and nutrient contents in shoots. In our opinion, combination of Cd-tolerant mutant SGECd and the strains 3841-PsMT1 or 3841-PsMT2 may be used as an original model for study of Cd tolerance mechanisms in legume-rhizobial symbiosis and possibilities for its application in phytoremediation or phytostabilization technologies.
获得了两种转基因的bv.菌株，3841 - PsMT1和3841 - PsMT2。这些菌株包含两种豌豆（L.）金属硫蛋白基因PsMT1和PsMT2的遗传构建体及编码序列，它们与PsENOD40基因的启动子区域融合。分析了这两种转基因菌株在豌豆野生型SGE和突变体SGECd（其特点是对镉（Cd）的耐受性增强且植物中镉积累增加）根部形成根瘤的能力。在不进行镉处理的情况下，接种3841、3841 - PsMT1或3841 - PsMT2菌株的野生型和突变体SGECd在根瘤的组织学和超微结构组织方面相似。接种3841菌株并暴露于0.5 μM CdCl₂的野生型SGE的根瘤，其衰老区扩大。这与经镉处理的突变体SGECd的根瘤形成鲜明对比，后者保持了其正常结构。对野生型SGE或突变体SGECd进行镉处理，均未导致由3841 - PsMT1和3841 - PsMT2菌株形成的根瘤的组织学结构发生显著改变。尽管在超微结构水平观察到一些异常，但3841 - PsMT1菌株根瘤中的异常比3841 - PsMT2形成的根瘤中的异常不那么明显。这两种转基因菌株对豌豆植株生长以及地上部分的镉和养分含量的影响也有所不同。我们认为，耐镉突变体SGECd与3841 - PsMT1或3841 - PsMT2菌株的组合可作为研究豆科植物 - 根瘤菌共生中镉耐受机制及其在植物修复或植物稳定技术中应用可能性的原始模型。
