Sphingobacterium thermophilum sp nov., of the phylum Bacteroidetes, isolated from compost

A Gram-negative bacterium, designated CKTN2(T), was isolated from compost. Cells of strain CKTN2(T) were strictly aerobic rods. The isolate grew at 20-50 degrees C (optimum 40-45 degrees C), but not below 15 degrees C or above 52 degrees C, and at pH 5.9-8.8 (optimum pH 7.0), but not below pH 5.4 or above pH 9.3. The DNA G+C content was 40.3 mol%. The predominant menaquinone was MK-7. The major fatty acids were iso-C-15:0 (45.2%), iso-C-17:0 3-OH (11.1 %) and C-18:0 (14.5%). Analysis of the 16S rRNA gene sequence of strain CKTN2(T) revealed that it is a member of the genus Sphingobacterium and is most closely related to Sphingobacterium alimentarium DSM 22362(T) (93.2% 16S rRNA gene sequence similarity). Strain CKTN2(T) could be distinguished from its closest phylogenetic relatives by different phenotypic characteristics. According to the phenotypic and genotypic characteristics, strain CKTN2(T) represents a novel species of the genus Sphingobacterium, for which the name Sphingobacterium thermophilum sp. nov. is proposed. The type strain is CKTN2(T) (=JCM 17858(T) =KCTC 23708(T)).