Flavimobilis rhizosphaerae sp. nov., isolated from rhizosphere soil of Spartina alterniflora

Abstract

A novel Gram-stain positive, facultatively anaerobic, motile, irregularly rod-shaped bacterium, designated GY 10621T, was isolated from rhizosphere soil of Spartina alterniflora in Beihai City, Guangxi Province, PR China, and characterized using a polyphasic taxonomic approach. GY 10621T was positive for catalase and oxidase. Growth occurred at 4–42 °C (optimum 30–37 °C), at pH 5.0–9.0 (optimum pH 7.0) and in the presence of 0–5% NaCl (w/v) (optimum 1–3%). The main menaquinones were MK-9 (H4) (92.2 %) and MK-10 (7.8 %). The major cellular fatty acids were anteiso-C15 : 0 and C14 : 0. The peptidoglycan was the type A4α (l-Lys-Ser-d-Glu). The polar lipids included four phosphoglycolipids, four glycolipids, an unidentified lipid and six unidentified phospholipids. The DNA G+C content of the type strain was 71.7 mol%. On the basis of the results of 16S rRNA gene analysis, the type strain of a species with a validly published name with the highest similarity to GY 10621T was Flavimobilis soli KCTC 13155T (97.16 %), followed by Sanguibacter suarezii NBRC 16159T (96.39 %). The calculated results indicated that compared with GY 10621T, the average nucleotide identity (ANI) values of three strains closely related to GY 10621T (the two aforementioned type strains and ‘ S. massiliensis ’ Marseille-P3815) were 74.18–94.97 %, and the digital DNA–DNA hybridization (dDDH) values were 20.3–60.6 %. The results of 16S rRNA-based and genome-based phylogenetic tree analysis indicated that GY 10621T should be assigned to the genus Flavimobilis . On the basis of evidence from polyphasic studies, GY 10621T should be designated as representing a novel species of the genus Flavimobilis , for which the name Flavimobilis rhizosphaerae sp. nov. is proposed. The type strain is GY 10621T (=CGMCC 1.17411T=KCTC 49515T).