Rhizobium yantingense sp. nov., a mineral-weathering bacterium

Abstract

A Gram-stain-negative, rod-shaped bacterial strain, H66T, was isolated from the surfaces of weathered rock (purple siltstone) found in Yanting, Sichuan Province, PR China. Cells of strain H66T were motile with peritrichous flagella. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain H66T belongs to the genus Rhizobium . It is closely related to Rhizobium huautlense SO2T (98.1 %), Rhizobium alkalisoli CCBAU 01393T (98.0 %) and Rhizobium cellulosilyticum ALA10B2T (98.0 %). Analysis of the housekeeping genes, recA, glnII and atpD, showed low levels of sequence similarity (<92.0 %) between strain H66T and other recognized species of the genus Rhizobium . The predominant components of the cellular fatty acids were summed feature 8 (C18 : 1ω7c and/or C18 : 1ω6c) and C16 : 0. The G+C content of strain H66T was 60.3 mol%. Strain H66T 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.1279 Rhizobium yantingense sp. nov. is proposed for this novel species. The type strain is H66T ( = CCTCC AB 2014007T = LMG 28229T).