Rhizobium flavum sp. nov., a triazophos-degrading bacterium isolated from soil under the long-term application of triazophos
A Gram-stain-negative, non-motile, pale yellow, rod-shaped bacterial strain, YW14T, was isolated from soil and its taxonomic position was investigated by a polyphasic study. Strain YW14T did not form nodules on three different legumes, and the nodD and nifH genes were not detected by PCR. Strain YW14T contained Q-10 as the predominant ubiquinone. The major cellular fatty acid was C18 : 1ω7c. Phylogenetic analyses based on 16S rRNA gene sequences and seven housekeeping gene sequences (recA, atpD, glnII, gyrB, rpoB, dnaK and thrC) showed that strain YW14T belonged to the genus Rhizobium . Strain YW14T showed 16S rRNA gene sequence similarity of 93.4–97.3 % to the type strains of recognized species of the genus Rhizobium . DNA–DNA relatedness between strain YW14T and the type strains of Rhizobium sullae IS123T and Rhizobium yanglingense CCBAU 71623T was 19.6–25.7 %, indicating that strain YW14T was distinct from them genetically. Strain YW14T could also be differentiated from these phylogenetically related species of the genus Rhizobium by various phenotypic properties. On the basis of phenotypic properties, phylogenetic distinctiveness and genetic data, strain YW14T is considered to represent a novel species of the genus Rhizobium , for which the name Rhizobium flavum sp. nov. is proposed. The type strain is YW14T ( = KACC 17222T = CCTCC AB2013042T).