Characterization of tropical tree rhizobia and description of Mesorhizobium plurifarium sp. nov. Int J Syst Bacteriol

Laboratoire de Microbiologie des Sols, ORSTOM, Dakar, Senegal, West Africa.
International journal of systematic bacteriology (Impact Factor: 2.27). 04/1998; 48 Pt 2(2):369-82. DOI: 10.1099/00207713-48-2-369
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ABSTRACT A collection of strains isolated from root nodules of Acacia species in Senegal was analysed previously by electrophoresis of total cell protein, auxanographic tests, rRNA-DNA hydridization, 16S rRNA gene sequencing, DNA base composition and DNA-DNA hybridization [de Lajudie, P., Willems, A., Pot, B. & 7 other authors (1994). Int J Syst Bacteriol 44, 715-733]. Strains from Acacia were shown to belong to two groups, Sinorhizobium terangae, and a so-called gel electrophoretic cluster U, which also included some reference strains from Brazil. Further taxonomic characterization of this group using the same techniques plus repetitive extragenic palindromic-PCR and nodulation tests is presented in this paper. Reference strains from Sudan and a number of new rhizobia isolated from nodules of Acacia senegal, Acacia tortilis subsp. raddiana and Prosopis juliflora in Senegal were included. As a result of this polyphasic approach, the creation of a new species, Mesorhizobium plurifarium, is proposed for a genotypically and phenotypically distinct group corresponding to the former cluster U and containing strains isolated from Acacia, Leucaena, Prosopis and Chamaecrista in West Africa (Senegal), East Africa (Sudan) and South America (Brazil). The type strain of Mesorhizobium plurifarium ORS 1032 has been deposited in the LMG collection as LMG 11892.

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Available from: Fatima Maria de Souza Moreira, Jan 04, 2014
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    • "The isolate PG10 representing PCR–RFLP Cluster 4 was related to Mesorhizobium showing the highest similarities with Mesorhizobium ciceri, Mesorhizobium loti and Mesorhizobium huakuii. It was previously reported that Prosopis juliflora in Senegal is nodulated by Mesorhizobium plurifarium (De Lajudie et al. 1998). "
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    ABSTRACT: Diversity of 50 bacterial isolates recovered from root nodules of Prosopis farcta grown in different arid soils in Tunisia, was investigated. Characterization of isolates was assessed using a polyphasic approach including phenotypic characteristics, 16S rRNA gene PCR--RFLP and sequencing, nodA gene sequencing and MLSA. It was found that most of isolates are tolerant to high temperature (40°C) and salinity (3%). Genetic characterization emphasizes that isolates were assigned to the genus Ensifer (80%), Mesorhizobium (4%) and non-nodulating endophytic bacteria (16%). Forty isolates belonging to the genus Ensifer were affiliated to Ensifer meliloti, Ensifer xinjiangense/Ensifer fredii and Ensifer numidicus species. Two isolates belonged to the genus Mesorhizobium. Eight isolates failing to renodulate their host plant were endophytic bacteria and belonged to Bacillus, Paenibacillus and Acinetobacter genera. Symbiotic properties of nodulating isolates showed a diversity in their capacity to infect their host plant and fix atmospheric nitrogen. Isolate PG29 identified as Ensifer meliloti was the most effective one. Ability of Prosopis farcta to establish symbiosis with rhizobial species confers an important advantage for this species to be used in reforestation programs. This study offered the first systematic information about the diversity of microsymbionts nodulating Prosopis farcta in the arid regions of Tunisia.
    Archives of Microbiology 02/2011; 193(6):385-97. DOI:10.1007/s00203-011-0683-z · 1.86 Impact Factor
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    • "Mesorhizobium and Bradyrhizobium have been isolated from nodules of various Acacia species [7] [8] [26]. The ecological distribution and abundance of the different Acacia species is mainly explained by altitude and rain fall gradients. "
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    Systematic and Applied Microbiology 12/2010; 34(3):216-26. DOI:10.1016/j.syapm.2010.09.006 · 3.31 Impact Factor
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    • "Broad host range mesorhizobia , such as NZP 2037, that are able to nodulate both groups of Lotus effectively [34] are rare. Many strains classified as M. loti have been poorly characterized [6] [31] and some are probably misclassified , which may explain the wide variability in total DNA–DNA homology [6], the different phylogenies [7] [50] and the great differences in N 2 -fixing effectiveness [3,32] detected among " M. loti " strains. Recently, strain " M. loti MAFF303099 " was re-classified as M. huakuii biovar loti [42]. "
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