Defluviimonas aestuarii sp. nov., a marine bacterium isolated from a tidal flat, and emended description of the genus Defluviimonas Foesel et al. 2011

Abstract

A novel Gram-staining-negative, strictly aerobic bacterium, designated BS14T, was isolated from a marine tidal flat of the South Sea in Korea. Colonies were opaque, white, smooth and circular on marine agar. Cells were moderately halophilic, non-motile rods showing catalase- and oxidase-positive reactions. Growth of strain BS14T was observed at 5–40 °C (optimum: 30 °C), pH 6.5–9.5 (optimum: 7.0–7.5) and 0–10 % (w/v) NaCl (optimum: 1–1.5 %). The G+C content of the genomic DNA was 61.6 mol%. Strain BS14T contained ubiquinone-10 (Q-10) as the sole respiratory quinone and summed feature 8 (comprising C18 : 1ω7c and/or C18 : 1ω6c), C18 : 0 3-OH, C10 : 0 3-OH and C18 : 0 as the major fatty acids. The polar lipid pattern comprised phosphatidylethanolamine, diphosphatidylglycerol, an unidentified aminolipid, an unidentified phospholipid and an unidentified polar lipid. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain BS14T formed a tight phylogenetic lineage with Defluviimonas denitrificans D9-3T with a bootstrap value of 100 %. The 16S rRNA gene sequence similarity between strain BS14T and D. denitrificans D9-3T was 97.4 % and their DNA–DNA relatedness was 19.1±3.6 %. Based on the phenotypic and genotypic studies, strain BS14T represents a novel species of the genus Defluviimonas , for which the name Defluviimonas aestuarii sp. nov. is proposed. The type strain is BS14T ( = KACC 16442T = JCM 18630T). An emended description of the genus Defluviimonas Foesel et al. 2011 is also proposed.