Marinobacter albus sp. nov., Isolated from Sand Sediment in a Coastal Intertidal Zone

A Gram-stain-negative bacterium with a rod-to-ovoid shape, named strain M216^T, was isolated from sand sediment from the coastal intertidal zone of Huludao, Liaoning Province, China. Growth was observed at 8-40 °C (optimal, 30 °C), pH 5.5-9.5 (optimal, pH 6.5) and 0.5-14.0% (w/v) NaCl (optimal, 6%). Strain M216^T possessed ubiquinone-9 as its sole respiratory quinone and phosphatidylethanolamine, diphosphatidylglycerol, phosphatidylglycerol, one unidentified aminophosphoglycolipid, one unidentified aminophospholipid, two unidentified phosphoglycolipids, three unidentified phospholipids and three unidentified glycolipids as the main polar lipids. C_12:0, C_16:0, C_12:0 3-OH, C_16:1 ω9c, C_18:1 ω9c and summed features 3 (C_16:1 ω7c and/or C_16:1 ω6c) were the major fatty acids (> 5%). The 16S rRNA gene sequence of strain M216^T exhibited high similarity to those of 'Marinobacter arenosus' CAU 1620^T and Marinobacter adhaerens HP15^T (99.3% and 98.5%, respectively) and less than 98.5% similarity to those of the other type strains. The ANI and dDDH values between the strain M216^T and 'Marinobacter arenosus' CAU 1620^T were 87.4% and 33.3%, respectively; these values were the highest among the other type strains but lower than the species threshold. The G+C content of strain M216^T was 58.3%. Genomic analysis revealed that strain M216^T harbors the major CAZymes of GH13, GH23, GH73, and PL5, which are responsible for polysaccharide degradation and the potential ability to reduce nitrate to ammonia. Through phenotypic, genotypic, and chemotaxonomic analyses, we proposed the name Marinobacter albus sp. nov., a novel species in the genus Marinobacter, with its type strain M216^T (= MCCC 1K08600^T = KCTC 82894^T).