Methylobacterium radiodurans sp. nov., a novel radiation-resistant Methylobacterium

A Gram-negative, aerobic, flagellated, rod-shaped, and pink-pigmented bacterium, strain 17Sr1-43 T , was isolated from a soil sample collected in Nowongu, Seoul, Korea. The isolate could grow at 18–37 °C (optimum, 28–30 °C), pH 6.0–8.0 (optimum, pH 7.0) and in the presence of 0–1.0% (w/v) NaCl (optimum, 0%) with aeration. The major cellular fatty acids were summed feature 8 (C 18:1 ω 7 c and/or C 18:1 ω 6 c ) and summed feature 2 (iso-C 16:1 I and/or C 14:0 3-OH). The predominant respiratory quinone was Q-10 and the major polar lipids were phosphatidylethanolamine, phosphatidylglycerol, phospholipid, and diphosphatidylglycerol. The G + C content of genomic DNA was 69.1 mol%. Strain 17Sr1-43 T was closely related to Methylobacterium gregans KACC 14808 T (98.4% 16S rRNA gene sequence similarity), Methylobacterium hispanicum KACC 11432 T (97.9%), and Methylobacterium phyllosphaerae CBMB27 T (96.1%). The complete genome of strain 17Sr1-43 T contains essential genes related to DNA repair processes including bacterial RecBCD dependent pathway and UmuCD system. Based on the phenotypic, genotypic, and chemotaxonomic characteristics, strain 17Sr1-43 T represents a novel species in the genus Methylobacterium , for which the name Methylobacterium radiodurans sp. nov. is proposed. The type strain is strain 17Sr1-43 T (= KCTC 52906 T = NBRC 112875 T ).