Description of Microbacterium neungamense sp. nov. isolated from a hot spring

Abstract

The Gram-positive, nonmotile, rod-shaped bacterium EF45044^T was isolated from a hot spring in Chungju, South Korea. The strain was able to grow at concentrations of 0‒5% (w/v) NaCl, at pH 6.0‒10.0 and in the temperature range of 18‒50 °C. Strain EF45044^T showed the highest 16S rRNA gene sequence similarity (98.2%) with Microbacterium ketosireducens DSM 12510^T, and the digital DNA‒DNA hybridization (dDDH), average amino acid identity (AAI), and average nucleotide identity (ANI) values were all lower than the accepted species threshold. Strain EF45044^T contained MK‒12 and MK‒13 as the predominant respiratory quinones and anteiso‒C_17:0, anteiso‒C_15:0, and iso‒C_16:0 as the major fatty acids. Diphosphatidylglycerol, phosphatidylglycerol, and glycolipid were detected as the major polar lipids. The cell-wall peptidoglycan contained ornithine. The DNA G + C content was 71.4 mol%. Based on the polyphasic data, strain EF45044^T (= KCTC 49703^T) presents a novel species of the genus Microbacterium, for which the name Microbacterium neungamense sp. nov. is proposed.

Keywords: Hot spring; Microbacterium; Microbacterium neungamense sp. nov; Polyphasic taxonomy.