A novel Gram-negative, aerobic, rod-shaped bacterium, RS19T, was isolated from rose rhizosphere soil. The strain was psychrophilic and showed good growth over a temperature range of 1-37 ℃. Colonies on TSB agar were circular, smooth, mucoid, convex with clear edges and yellow. Phylogenetic analysis based on 16S rRNA gene sequences characterized RS19T in the genus Dyadobacter and showed that strain RS19T was most closely related to Dyadobacter psychrophilus CGMCC 1.8951T (97.4%) and Dyadobacter alkalitolerans CGMCC 1.8973T (97.1%). The average nucleotide identity values to the closest related species type strains were less than 84.0%. The DNA G + C content was 43.1 mol%, and the predominant respiratory menaquinone was MK-7. The major fatty acids were summed features 3 (C16:1ω7c and/or C16:1ω6c), iso-C15:0, C16:1ω5c and iso-C17:0 3-OH. Based on genotypic, phenotypic and chemotaxonomic data, strain RS19T is different from closely related species of the genus Dyadobacter. RS19T represents a novel species within the genus Dyadobacter, for which the name Dyadobacter luteus sp. nov. is proposed. The type strain is RS19T (= CGMCC 1.13719T = ACCC 60381T = JCM 32940T).
Keywords: Cytophagaceae; Dyadobacter luteus; Rose rhizosphere soil.