Thalassotalea mangrovi sp. nov., a bacterium isolated from marine mangrove sediment

A novel Gram-stain-negative, strictly aerobic bacterium that has a rod-like shape with a single polar flagellum in the exponential phase of growth and a spherical or ovoid shape without a flagellum in the stationary phase was isolated from a mangrove wetland sediment sample collected at Beilun Estuary National Nature Reserve, Guangxi Province, PR China and designated strain ZS-4(T). This strain grew optimally at pH 6.0-8.0, at a temperature of 37 degrees C and in the presence of 3-4% (w/v) NaCl. Its polar lipid profile included phosphatidylethanolamine, phosphatidylglycerol, one unidentified aminophospholipid and two uncharacterized lipids. Ubiquinone 8 (Q-8) was the sole respiratory quinone and the cellular fatty acids were dominated by C-17(:1)omega 8c and C-16(:0). A phylogenetic analysis based on the 16S rRNA gene sequence showed that strain ZS-4(T) exhibited its highest similarities to the type strains Thalassotalea litorea HMF4135(T) (97.8 %) and Thalassotalea ponticola GJSW-36(T) (95.9 %). A whole genome-level comparison of strain ZS-4(T) with T. litorea MCCC 1 K03283(T) revealed an average nucleotide identity value of 75.6 % and a calculated DNA-DNA hybridization value of 19.6 %. In addition, the genomic DNA G+C content of strain ZS-4(T) was 45.9 mol%. Thus, based on analyses of its morphology, physiology, fatty acid composition and 16S rRNA gene sequence, strain ZS-4(T) should be considered a novel species of the genus Thalassotalea, with the proposed name Thalassotaleamangrovi sp. nov. The type strain is ZS-4 (T) (=KCTC 72399(T)=MCCC 1K03630(T)).