Methylobacterium phyllosphaerae sp nov., a pink-pigmented, facultative methylotroph from the phyllosphere of rice

A pink-pigmented, aerobic, facultatively methylotrophic bacterial strain, CBMB27(T), isolated from leaf tissues of rice (Oryza sativa L. 'Dong-Jin'), was analysed using a polyphasic taxonomic approach. Comparative 16S rRNA gene sequence-based phylogenetic analysis placed the strain in a clade with the species Methylobacterium oryzae, Methylobacterium fujisawaense and Methylobacterium mesophilicum; strain CBMB27(T) showed sequence similarities of 98.3, 98.5 and 97.3%, respectively, to the type strains of these three species. DNA-DNA hybridization experiments revealed low levels (< 38%) of DNA-DNA relatedness between strain CBMB27(T) and its closest relatives. The sequence of the 1-aminocyclopropane-1-carboxylate deaminase gene (acdS) in strain CBMB27(T) differed from those of close relatives. The major fatty acid of the isolate was C-18: (1)omega 7c and the G + C content of the genomic DNA was 66.8 mol%. Based on the results of 16S rRNA gene sequence analysis, DNA-DNA hybridization, and physiological and biochemical characterization, which enabled the isolate to be differentiated from all recognized species of the genus Methylobacterium, it was concluded that strain CBMB27(T) represents a novel species in the genus Methylobacterium for which the name Methylobacterium phyllosphaerae sp. nov. is proposed (type strain CBMB27(T) =LMG 24361(T) =KACC 11716(T) =DSM 19779(T)).