Dataset Information

Nodulation of Sesbania species by Rhizobium (Agrobacterium) strain IRBG74 and other rhizobia.

ABSTRACT: Concatenated sequence analysis with 16S rRNA, rpoB and fusA genes identified a bacterial strain (IRBG74) isolated from root nodules of the aquatic legume Sesbania cannabina as a close relative of the plant pathogen Rhizobium radiobacter (syn. Agrobacterium tumefaciens). However, DNA:DNA hybridization with R. radiobacter, R. rubi, R. vitis and R. huautlense gave only 44%, 5%, 8% and 8% similarity respectively, suggesting that IRBG74 is potentially a new species. Additionally, it contained no vir genes and lacked tumour-forming ability, but harboured a sym-plasmid containing nifH and nodA genes similar to those in other Sesbania symbionts. Indeed, IRBG74 effectively nodulated S. cannabina and seven other Sesbania spp. that nodulate with Ensifer (Sinorhizobium)/Rhizobium strains with similar nodA genes to IRBG74, but not species that nodulate with Azorhizobium or Mesorhizobium. Light and electron microscopy revealed that IRBG74 infected Sesbania spp. via lateral root junctions under flooded conditions, but via root hairs under non-flooded conditions. Thus, IRBG74 is the first confirmed legume-nodulating symbiont from the Rhizobium (Agrobacterium) clade. Cross-inoculation studies with various Sesbania symbionts showed that S. cannabina could form fully effective symbioses with strains in the genera Rhizobium and Ensifer, only ineffective ones with Azorhizobium strains, and either partially effective (Mesorhizobium huakii) or ineffective (Mesorhizobium plurifarium) symbioses with Mesorhizobium. These data are discussed in terms of the molecular phylogeny of Sesbania and its symbionts.

SUBMITTER: Cummings SP

PROVIDER: S-EPMC7163632 | biostudies-literature | 2009 Oct

REPOSITORIES: biostudies-literature

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Nodulation of Sesbania species by Rhizobium (Agrobacterium) strain IRBG74 and other rhizobia.

Cummings Stephen P SP Gyaneshwar Prasad P Vinuesa Pablo P Farruggia Frank T FT Andrews Mitchell M Humphry David D Elliott Geoffrey N GN Nelson Andrew A Orr Caroline C Pettitt Deborah D Shah Gopit R GR Santos Scott R SR Krishnan Hari B HB Odee David D Moreira Fatima M S FM Sprent Janet I JI Young J Peter W JP James Euan K EK

Environmental microbiology 20090625 10

Concatenated sequence analysis with 16S rRNA, rpoB and fusA genes identified a bacterial strain (IRBG74) isolated from root nodules of the aquatic legume Sesbania cannabina as a close relative of the plant pathogen Rhizobium radiobacter (syn. Agrobacterium tumefaciens). However, DNA:DNA hybridization with R. radiobacter, R. rubi, R. vitis and R. huautlense gave only 44%, 5%, 8% and 8% similarity respectively, suggesting that IRBG74 is potentially a new species. Additionally, it contained no vir ...[more]

PMID: 19555380

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Dataset Information

Nodulation of Sesbania species by Rhizobium (Agrobacterium) strain IRBG74 and other rhizobia.

Publications

Nodulation of Sesbania species by Rhizobium (Agrobacterium) strain IRBG74 and other rhizobia.

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