Sphingobacterium chungjuense sp. nov., isolated from a freshwater lake

A Gram-stain-negative, rod-shaped, aerobic, non-flagellated, chemoheterotrophic bacterium, designated strain IMCC25678^T, was isolated from an artificial freshwater reservoir, Chungju Lake, in the Republic of Korea. The 16S rRNA gene sequence analysis indicated that strain IMCC25678^T belongs to the genus Sphingobacterium with ≤98.7 % sequence similarities to Sphingobacterium species. Whole genome sequencing of strain IMCC25678^T revealed a 3.9 Mbp genome size with a DNA G+C content of 42.2 mol%. The IMCC25678^T genome shared ≤89.7 % average nucleotide identity and ≤21.4 % digital DNA-DNA hybridization values with closely related species of the genus Sphingobacterium, indicating that the strain represents a novel species. Summed feature 3 (C_16 : 1  ω6c and/or C_16 : 1  ω7c), iso-C_15 : 0 and iso-C_17 : 0 3-OH were found to be the predominant cellular fatty acid constituents in the strain. The major respiratory quinone was MK-7. The major polar lipids were phosphatidylethanolamine, one unidentified phosphoglycolipid, one unidentified sphingolipid and three unidentified polar lipids. Based on the phylogenetic and phenotypic characteristics, strain IMCC25678^T was considered to represent a novel species within the genus Sphingobacterium, for which the name Sphingobacterium chungjuense sp. nov. is proposed. The type strain is IMCC25678^T (=KACC 19485^T=NBRC 113130^T).