Deinococcus taeanensis sp. nov., a Radiation-Resistant Bacterium Isolated from a Coastal Dune.

A Gram-stain-negative, nonspore-forming, nonmotile, aerobic, rod-shaped, and very pale orange-colored bacterial strain, designated TS293, was isolated from a sand sample obtained from a coastal dune after exposure to 3kGy of gamma (γ)-radiation. Phylogenetic analysis based on the 16S rRNA gene sequences revealed that the isolate was a member of the genus Deinococcus and clustered with D. deserti VCD115. The genome of strain TS293 was 4.62 Mbp long (68.2% G + C content and 4124 predicted genes) divided into a 2.86Mb main chromosome and five plasmids. Many genes considered to be important to the γ-radiation and oxidative stress resistance of Deinococcus were conserved in TS293, but genome features that could differentiate TS293 from D. deserti and D. radiodurans, the type species of the Deinococcus genus, were also detected. Strain TS293 showed resistance to γ-radiation with D values (i.e., the dose required to reduce the bacterial population by tenfold) of 3.1kGy. The predominant fatty acids of strain TS293 were summed feature 3 (C ω6c and/or C ω7c) and iso-C. The major polar lipids were two unidentified phosphoglycolipids and one unidentified glycolipid. The main respiratory quinone was menaquinone-8. Based on the phylogenetic, genomic, physiological, and chemotaxonomic characteristics, strain TS293 represents a novel species, for which the name Deinococcus taeanensis sp. nov. is proposed. The type strain is TS293 (= KCTC 43191 = JCM 34027).