Departamento de Genética, Instituto de Biociências, Universidade Federal do Rio Grande do Sul , Porto Alegre, RS Brasil.
Braz J Microbiol. 2010 Oct;41(4):1142-51. doi: 10.1590/S1517-838220100004000036. Epub 2010 Dec 1.
Bradyrhizobium elkanii is successfully used in the formulation of commercial inoculants and, together with B. japonicum, it fully supplies the plant nitrogen demands. Despite the similarity between B. japonicum and B. elkanii species, several works demonstrated genetic and physiological differences between them. In this work Representational Difference Analysis (RDA) was used for genomic comparison between B. elkanii SEMIA 587, a crop inoculant strain, and B. japonicum USDA 110, a reference strain. Two hundred sequences were obtained. From these, 46 sequences belonged exclusively to the genome of B. elkanii strain, and 154 showed similarity to sequences from B. japonicum genome. From the 46 sequences with no similarity to sequences from B. japonicum, 39 showed no similarity to sequences in public databases and seven showed similarity to sequences of genes coding for known proteins. These seven sequences were divided in three groups: similar to sequences from other Bradyrhizobium strains, similar to sequences from other nitrogen-fixing bacteria, and similar to sequences from non nitrogen-fixing bacteria. These new sequences could be used as DNA markers in order to investigate the rates of genetic material gain and loss in natural Bradyrhizobium strains.
慢生根瘤菌被成功应用于商业接种剂的配方中，与大豆根瘤菌一起，完全满足了植物对氮的需求。尽管大豆根瘤菌和慢生根瘤菌属非常相似，但已有多项研究证明了它们之间存在遗传和生理上的差异。在这项研究中，我们使用代表性差异分析（RDA）对作物接种剂菌株 SEMIA 587 和参考菌株 USDA 110 进行了基因组比较。共获得了 200 个序列。其中，46 个序列仅属于慢生根瘤菌菌株的基因组，而 154 个序列与大豆根瘤菌基因组的序列具有相似性。在这 46 个与大豆根瘤菌基因组无相似性的序列中，39 个与公共数据库中的序列无相似性，7 个与编码已知蛋白质的基因序列相似。这 7 个序列分为三组：与其他慢生根瘤菌菌株的序列相似，与其他固氮细菌的序列相似，与非固氮细菌的序列相似。这些新序列可以用作 DNA 标记，以研究自然条件下慢生根瘤菌菌株遗传物质获得和丢失的速率。
