Sphingomonas yantingensis sp. nov., a mineral-weathering bacterium isolated from purplish paddy soil.

A novel type of mineral-weathering bacterium was isolated from purplish soils collected from Yanting (Sichuan, south-western China). Cells of strain 1007(T) were Gram-stain-negative and rod-shaped, motile and yellow-pigmented. The isolate was strictly aerobic, catalase- and oxidase-positive, and grew optimally at 28-30 °C and pH 6.0-7.0. The genomic DNA G+C content of strain 1007(T) was 67±0.7 mol%. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain 1007(T) belonged to the genus Sphingomonas and was most closely related to Sphingomonas pruni IFO 15498(T) (97.3 %), Sphingomonas mali IFO 15500(T) (97.2 %), Sphingomonas japonica KC7(T) (97.2 %) and Sphingomonas koreensis JSS26(T) (97.0 %). This affiliation of strain 1007(T) to the genus Sphingomonas was confirmed by the presence of Q-10 as the major ubiquinone, sphingoglycolipid, C14 : 0 2-OH and by the absence of 3-hydroxy fatty acids. The major polyamine was homospermidine. The main cellular fatty acids included summed feature 8 (comprising C18 : 1ω7c and/or C18 : 1ω6c) and C16 : 0. Based on the low level of DNA-DNA relatedness (ranging from 26.1 % to 58.7 %) to these type strains of species of the genus Sphingomonas and unique phenotypic characteristics, strain 1007(T) represents a novel species of the genus Sphingomonas, for which the name Sphingomonas yantingensis sp. nov. is proposed. The type strain is 1007(T) ( = DSM 27244(T) = JCM 19201(T) = CCTCC AB 2013146(T)).