Paramicrobacterium salitolerans sp. nov. isolated from the agricultural soil and Microbacterium fluminis sp. nov. isolated from the Han River, South Korea.

Abstract

Two novel bacterial species, designated as CJ85T and CJ88T, were isolated from the agricultural soil and the Han River, South Korea, respectively. Cells of both strains were Gram-staining-positive, short rod-shaped, non-motile, and yellow-pigmented. Strain CJ85T exhibited optimal growth in tryptic soy broth at 37°C and pH 7.0 in the absence of NaCl. Strain CJ88T showed optimal growth in lysogeny broth at 30°C and pH 7.0 in the absence of NaCl. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain CJ85T belonged to the genus Paramicrobacterium, showing the highest sequence similarity to Paramicrobacterium fandaimingii HY82T (97.6%). Strain CJ88T was assigned to the genus Microbacterium, with the highest sequence similarity to Microbacterium azadirachtae DSM 23848T (98.5%). The DNA G + C content was 64.8% for strain CJ85T and 70.5% for strain CJ88T. The genome-based analyses, including phylogenomic tree, digital DNA-DNA hybridization, and average nucleotide identity, clearly indicated that these strains represent novel species within their respective genera. The major fatty acids of both strains were anteiso-C15:0, anteiso-C17:0, and iso-C16:0. Based on the polyphasic taxonomy study, strains CJ85T and CJ88T represent novel species of the genera Paramicrobacterium and Microbacterium, respectively, for which names Paramicrobacterium salitolerans sp. nov. and Microbacterium fluminis sp. nov. are proposed. The type strains CJ85T (= KACC 23064T = JCM 36217T) and CJ88T (= KACC 24080T = JCM 38050T).