A Gram-stain-negative, non-motile and ovoid or rod-shaped bacterial strain, DBTF-13T, which was isolated from a tidal flat sediment of the Yellow Sea in South Korea, was characterized taxonomically. Strain DBTF-13T grew optimally at 25-30 °C and pH 7.0-8.0, and in the presence of 2.0 % (w/v) NaCl. The phylogenetic trees based on 16S rRNA gene sequences revealed that strain DBTF-13T formed an evolutionary lineage independent of other genera, including the genera Pseudooctadecabacter and Octadecabacter. Strain DBTF-13T exhibited 16S rRNA gene sequence similarity values of 96.9 % to the type strain of Pseudooctadecabacter jejudonensis, and of 95.8-96.5 % to the type strains of Octadecabacter species. Strain DBTF-13T contained Q-10 as the predominant ubiquinone and C18 : 1ω7c and C16 : 0 as the major fatty acids. The major polar lipids of strain DBTF-13T were phosphatidylcholine, phosphatidylglycerol, one unidentified aminolipid and one unidentified lipid. The DNA G+C content of strain DBTF-13T was 61.6 mol%. The chemotaxonomic data and other differential phenotypic properties made it reasonable to differentiate strain DBTF-13T from the genera Pseudooctadecabacter and Octadecabacter. On the basis of the data presented, strain DBTF-13T constitutes a new genus and species within the class Alphaproteobacteria, for which the name Aestuariibius insulae gen. nov., sp. nov. is proposed. The type strain is DBTF-13T (=KACC 19432T=NBRC 113038T).
Keywords: Aestuariibius insulae; novel genus; novel species; polyphasic taxonomy; tidal flat sediment.