Four bacterial strains isolated from root nodules of Phaseolus vulgaris, Mimosa pudica and Indigofera spicata plants grown in the Yunnan province of China were identified as a lineage within the genus Rhizobium according to the analysis of 16S rRNA gene sequences, sharing most similarity with Rhizobium lusitanum P1-7T (99.1 % sequence similarity) and Rhizobium rhizogenes IAM 13570T (99.0 %). These strains also formed a distinctive group from the reference strains for defined species of the genus Rhizobium in a polyphasic approach, including the phylogenetic analyses of the 16S rRNA gene and housekeeping genes (recA, atpD, glnII), DNA–DNA hybridization, BOX-PCR fingerprinting, phenotypic characterization, SDS-PAGE of whole-cell proteins, and cellular fatty acid profiles. All the data obtained in this study suggested that these strains represent a novel species of the genus Rhizobium, for which the name Rhizobium vallis sp. nov. is proposed. The DNA G+C content (mol%) of this species varied between 60.9 and 61.2 (Tm). The type strain of R. vallis sp. nov. is CCBAU 65647T ( = LMG 25295T = HAMBI 3073T), which has a DNA G+C content of 60.9 mol% and forms effective nodules on Phaseolus vulgaris.
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Funding
This study was supported by the:
State Key Basic Research and Development Plan of China
(Award 2006CB100206)
National Program for Basic S & T Platform Construction
(Award 2005DKA21201-10)
National Natural Science Foundation of China
(Award 30400001 and 30670001)
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