Aestuariihabitans beolgyonensis gen. nov., sp. nov., a novel alphaproteobacterium isolated from tidal flat sediment.

A Gram-negative, non-motile and rod-shaped bacterial strain, designated BB-MW15(T), was isolated from a tidal flat of the southern coast of the Korean peninsula, and its taxonomic position was investigated by using a polyphasic taxonomic approach. Strain BB-MW15(T) grew optimally at 30 °C, at pH 7.0-8.0 and in the presence of 2-3 % (w/v) NaCl. Strain BB-MW15(T) exhibited the highest 16S rRNA gene sequence similarity values to the type strains of Marivita byunsanensis (96.8 %), Thalassobius maritimus (96.6 %), Sulfitobacter marinus (96.4 %) and Marinovum algicola (96.3 %). Neighbour-joining, maximum-likelihood and maximum-parsimony phylogenetic trees based on 16S rRNA gene sequences revealed that strain BB-MW15(T) forms an independent lineage within the evolutionary radiation encompassed by the Roseobacter clade of the class Alphaproteobacteria. Strain BB-MW15(T) contained Q-10 as the predominant ubiquinone and C18:1 ω7c as the predominant fatty acid. The major polar lipids detected in strain BB-MW15(T) were phosphatidylcholine, phosphatidylglycerol, one unidentified aminolipid and one unidentified lipid. The DNA G+C content of strain BB-MW15(T) is 62.7 mol%. Based on phylogenetic, chemotaxonomic and other phenotypic characteristics, strain BB-MW15(T) represents a new genus and a new species within Alphaproteobacteria, for which the name Aestuariihabitans beolgyonensis gen. nov., sp. nov. is proposed. The type strain of A. beolgyonensis is BB-MW15(T) (= KCTC 32324(T) = CCUG 63829(T)).