Deinococcus radioresistens sp. nov., a UV and gamma radiation-resistant bacterium isolated from mountain soil

Abstract

Two Gram-negative, non-motile, short rod-shaped bacterial strains, designated as 8AT and 28A, were isolated from Mount Deogyusan, Jeonbuk Province, South Korea. The isolates were analyzed by a polyphasic approach, revealing variations in their phenotypic characters but high DNA–DNA hybridisation values reciprocally, confirming that they belong to the same species. Both the isolates also showed a high resistance to UV compared with Deinococcus radiodurans, and a gamma-radiation resistance similar to other members of the genus Deinococcus. Phylogenetic analysis with the 16S rRNA gene sequences of closely related species indicated their similarities were below 97 %. Chemotaxonomic data showed the most abundant fatty acids to be C16:1ω7c and C16:0. The strains can be distinguished from closely related species by the production of esterase (C4) and α-galactosidase, and by their ability to assimilate l-alanine, l-histidine and N-acetyl-d-glucosamine. Based on the phenotypic, phylogenetic, and chemotaxonomic data, the isolates represent a novel species of the genus Deinococcus, for which the name Deinococcusradioresistens sp. nov. is proposed. The type strain is 8AT (KEMB 9004-109T = JCM 19777T), and a second strain is 28A (KEMB 9004-113 = JCM 19778).