Rhizobium yantingense sp nov., a mineral-weathering bacterium

A Gram-stain-negative, rod-shaped bacterial strain, H66(T), was isolated from the surfaces of weathered rock (purple siltstone) found in Yanting, Sichuan Province, PR China. Cells of strain H66(T) were motile with peritrichous flagella. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain H66(T) belongs to the genus Rhizobium. It is closely related to Rhizobium huautlense SO2T (98.1%), Rhizobium alkalisoli CCBAU 01393(T) (98.0%) and Rhizobium cellulosilyticum ALA10B(2)(T) (98.0%). Analysis of the housekeeping genes, recA, glnll and atpD, showed low levels of sequence similarity (<92.0 %) between strain H66(T) and other recognized species of the genus Rhizobium. The predominant components of the cellular fatty acids were summed feature 8 (C-(18:1)omega 7c and/or C-18:1 omega 6c) and C-16:0. The G+C content of strain H66(T) was 60.3 mol%. Strain H66(T) is suggested to be a novel species of the genus Rhizobium based on the low levels of DNA-DNA relatedness (ranging from 14.3% to 40.0%) with type strains of species of the genus Rhizobium and on its unique phenotypic characteristics. The namehttp://dx.doi.org/10.1601/nm.1279Rhizobium yantingense sp. nov. is proposed for this novel species. The type strain is H66(T) (=CCTCC AB 2014007(T)=LMG 28229(T)).