Pseudomonas pratensis sp. nov., Isolated from Grassland Soil from Inner Mongolia, China.

A novel bacterial strain, designated MHJ-10J, was isolated from a soil sample obtained from a grassland in Inner Mongolia, China. MHJ-10J strain could grow at 4-37 °C (optimum: 30 °C) and pH 4-9 (optimum: pH 6), as well as in the presence of 0-6% NaCl (optimum: 1%). Cells of strain MHJ-10J are Gram-negative, rod-shaped, and motile. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain MHJ-10J was most closely related to Pseudomonas lutea OK2 (98.5% 16S rRNA gene sequence similarity). The values of the average nucleotide identities (ANI) and digital DNA-DNA hybridization (dDDH) between strain MHJ-10J and its related species were all below 80.5% and 24.4%, respectively, which are significantly lower than the thresholds of 95% for ANI and 70% for DDH for species delineation. The genomic G + C content of the MHJ-10J strain is 64.8 mol%. Based on the phenotypic, genotypic, chemotaxonomic, and phylogenetic analyses, strain MHJ-10J can be assigned to the genus Pseudomonas. In this study, we propose that strain MHJ-10J be classified as a novel species belonging to the genus Pseudomonas with the species name Pseudomonas pratensis sp. nov. The type strain of the proposed novel species is MHJ-10J (= KCTC 82206 = CGMCC 17322).