Demequina activiva sp. nov., isolated from a tidal flat

A Gram-stain-positive, facultatively anaerobic, non-spore-forming, non-flagellated and rod-shaped or ovoid bacterial strain, designated BS-12M(T), was isolated from a tidal flat sediment on the South Sea, South Korea. Strain BS-12M(T) grew optimally at 35 °C, at pH 7.0-8.0 and in the presence of 2.0% (w/v) NaCl. The neighbour-joining phylogenetic tree based on 16S rRNA gene sequences revealed that strain BS-12M(T) fell within the cluster comprising the type strains of species of the genus Demequina, joining the type strain of Demequina aestuarii with which it shared the highest sequence similarity (98.6%). It exhibited 16S rRNA gene sequence similarity of 96.1-97.9% to the type strains of other species of the genus Demequina. The peptidoglycan type of strain BS-12M(T) was A4β based on L-Orn -L-Ser -D-Glu. Strain BS-12M(T) contained demethylmenaquinone-9(H4) as the major menaquinone and anteiso-C15:0 and C16:0 as the major fatty acids. The major polar lipids of strain BS-12M(T) were phosphatidylinositol and phosphatidylinositolmannoside. The DNA G+C content of strain BS-12M(T) was 70.7 mol% and its DNA-DNA relatedness values with the type strains of five phylogenetically related species of the genus Demequina were 15-34%. Differential phenotypic properties, together with phylogenetic and genetic distinctiveness, revealed that strain BS-12M(T) is separate from other species of the genus Demequina. On the basis of the data presented, strain BS-12M(T) is considered to represent a novel species of the genus Demequina, for which the name Demequina activiva sp. nov. is proposed. The type strain is BS-12M(T) ( =KCTC 29674(T) = NBRC 110675T).