Abstract

A pink-pigmented bacterium, designated SW08-7T was isolated from the drinking water of a water purifier. Cells were Gram-negative, rod-shaped, strictly aerobic, and non-spore-forming. It grew optimally at 25°C, pH 6~7. Phylogenetic analysis based on 16S rRNA gene sequence showed that strain SW08-7T belongs to the genus Methylobacterium. The highest 16S rRNA gene sequence similarities were found to Methylobacterium mesophilicum JCM 2829T (96.9%), Methylobacterium brachiatum B0021T (96.9%), Methylobacterium phyllosphaerae CBMB27T (96.6%), Methylobacterium radiotolerans JCM 2831T (96.6%), and Methylobacterium hispanicum GP34T (96.5%). DNA-DNA hybridization experiment revealed low-level (28.5%) of DNA- DNA relatedness between strain SW08-7T and Methylobacterium hispanicum. The genomic DNA G+C content was 68.9 mol% and the major isoprenoid quinone was Q-10. The major cellular fatty acid of strain SW08-7T was C18:1 ω7c (79.8±2.1%). Results of phylogenetic, phenotypic, and biochemical analyses revealed that strain SW08-7T could be classified as representing a novel species of genus Methylobacterium, for which the name Methylobacterium dankookense sp. nov. is proposed. The type strain is SW08-7T (=KCTC 22512T =DSM 22415T).

• Keywords: drinking water; alphaproteobacteria; Methylobacterium