Hymenobacter rubidus sp. nov., bacterium isolated from a soil

Strain DG7B^T was isolated from a soil sample collected in Seoul, Republic of Korea and was observed to be a gram-negative, short-rod shaped and non-motile bacterium. Its 16S rRNA gene sequence is closely related to those of Hymenobacter terrae DG7A^T (97.8 % similarity), H. soli PB17^T (97.5 %), H. glaciei VUG-A130^T (96.4 %), H. saemangeumensis GSR0100^T (95.7 %), H. ruber PB156^T (95.3 %), and H. antarcticus VUG-A42aa^T (95.3 %). The low levels of DNA–DNA relatedness (<50.3 %) with the above species identified strain DG7B^T as a novel species in the genus Hymenobacter. The genomic DNA G+C content was determined to be 54.9 %. Growth of strain DG7B^T was observed at 12–30 °C (optimum at 25 °C) and pH 6.0–11.0 (optimum at pH 7). The cells tolerate <0.5 % NaCl. A UV-visible scan of an ethanol extract of the whole cell pigment showed absorbance peaks at 264.5, 320.0, and 481.5 nm, so the pigment type was determined to be 2′-hydroxyflexixanthin. Chemotaxonomic data showed that strain DG7B^T possesses menaquinone-7 as the predominant isoprenoid quinone, sym-homospermidine as the major polyamine, phosphatidylethanolamine as the predominant polar lipid and iso-C_15:0, anteiso-C_15:0 and summed feature 3 (C_16:1ω7c/C_16:1ω7c) as the major fatty acids. Strain DG7B^T showed low-level resistance to ultraviolet C. Based on the polyphasic analysis, it is concluded that strain DG7B^T (=KCTC 32553^T = KEMB 9004-166^T = JCM 30008^T) should be classified as the type strain of a novel Hymenobacter species, for which the name Hymenobacter rubidus sp. nov. is proposed.