
Full text loading...
Two novel strains, THG-C26T and THG-C31T, were characterized using a polyphasic approach to determine their taxonomic positions. These two isolates were aerobic, Gram-stain-positive, non-motile, non-spore-forming and rod-shaped. 16S rRNA gene sequences and phenotypic features including chemotaxonomic characteristics indicated that the two isolates clearly represented members of the genus Microbacterium . The quinone systems of strains THG-C26T and THG-C31T contained MK-12/MK-13 as major menaquinones. The diamino acid in cell-wall hydrolysates of the two strains was ornithine. The major fatty acids were iso-C16 : 0, anteiso-C15 : 0 and anteiso-C17 : 0. The polyamine pattern had spermidine as the predominant component. The major polar lipids were phosphatidylglycerol, diphosphatidylglycerol and unidentified glycolipids. Phenotypic characteristics supported the affiliation of strains THG-C26T and THG-C31T to the genus Microbacterium . Chemotaxonomic data and DNA–DNA relatedness values allowed differentiation of these strains from other species of the genus Microbacterium with validly published names. Strains THG-C26T and THG-C31T showed highest 16S rRNA gene sequence similarities with Microbacterium resistens DMMZ 1710T (98.5 %) and Microbacterium trichothecenolyticum IFO 15077T (98.8 %), respectively, and the 16S rRNA gene sequence similarity between them was 99.0 %. DNA–DNA hybridization values between the novel isolates and strains of other species of the genus Microbacterium with validly published names were 4–25 %. Therefore, strains THG-C26T and THG-C31T are considered to represent two novel species of the genus Microbacterium , for which the names Microbacterium kyungheense sp. nov. [type strain THG-C26T ( = KACC 17124T = JCM 18735T)] and Microbacterium jejuense sp. nov. [type strain THG-C31T ( = KACC 17123T = JCM 18734T)] are proposed.