A Gram-stain-negative, aerobic and slightly halophilic bacterium was isolated from the South China Sea, and was subjected to characterization using a polyphasic taxonomic approach. Cells of the isolate, designated NH83T , were non-motile and rod-shaped. On the basis of 16S rRNA gene sequence analysis, strain NH83T was closely related to members of the genera Aureisphaera (with sequence similarity of 92.9 %), Jejudonia (92.8 %), Marixanthomonas (92.6 %), Altuibacter (92.6 %), Ulvibacter (91.5-91.9 %), Gilvibacter (91.8 %) and Aequorivita (89.6-91.2 %), all of which belong to the family Flavobacteriaceae. Phylogenetic analysis indicated that it represented an independent lineage and its closest relatives belonged to the genus Marixanthomonas. The sole respiratory quinone was MK-6. The major polar lipids were phosphatidylethanolamine, two aminolipids, one aminophospholipid and one unidentified lipid. The principal fatty acids were branched fatty acids, including iso-C 15 : 0 , iso-C 17 : 0 3-OH, iso-C 16 : 0 , iso-C 15 : 1 G and summed feature 3 (iso-C 15 : 0 2-OH and/or C 16 : 1 !7c). The genomic DNA G+C content was 41.0 mol%. Strain NH83T was positive for hydrolysis of aesculin, gelatin

A Gram-stain-negative, aerobic, non-motile and rod-shaped bacterium, designated B1, was isolated from deep-sea sediment collected from the South Atlantic Ocean. Cells of strain B1 grew in medium containing 0.5-6.0 % (w/v) NaCl (optimum 1.0-2.0 %), at pH 5.5-7.5 (optimum pH 7.0) and at 15-37 °C (optimum 30 °C). Aesculin, starch and Tweens 20, 40 and 60 were hydrolysed. The strain was able to grow in medium containing a high concentration of Co (10 mM). The 16S rRNA gene sequence of strain B1 shared high similarity with respect to Maribacter orientalis DSM 16471 (97.7 %), and exhibited less than 97.0 % sequence similarity with the type strains of other species with validly published names. Phylogenetic analyses revealed that strain B1 fell within the cluster comprising Maribacter species and formed an independent lineage. The average nucleotide identity and in silico DNA-DNA hybridization values between strain B1 and M. orientalis DSM 16471 were 72.0 % and 17.6 %, respectively. Strain B1 contained menaquinone 6 (MK-6) as the sole isoprenoid quinone and iso-C17 : 0 3-OH, iso-C15 : 0 and iso-C15 : 1 G as the predominant cellular fatty acids. The major polar lipids were phosphatidylethanolamine, one unidentified aminolipid and two unidentified lipids. The DNA G+C content was 39.7 mol%. According to the phylogenetic, chemotaxonomic and phenotypic data, B1 represents a novel species of the genus Maribacter, for which the name Maribacter cobaltidurans sp. nov. is proposed. The type strain is B1 (=CGMCC 1.15508=KCTC 52882=MCCC 1K03318).

A Gram-stain-negative bacterium, designated NH169-3, was isolated from a surface seawater sample of the South China Sea and subjected to a taxonomic polyphasic investigation. Strain NH169-3 was strictly aerobic, non-motile, non-spore-forming and rod-shaped. The colony was 1.0-2.0 mm in diameter after the growth on marine agar at 30 °C for 72 h. The centre of the colony was smooth, circular, convex and brown with a transparent periphery. Strain NH169-3 was able to grow at temperatures between 4-40 °C (optimum, 37 °C), pH 5.5-9.0 (pH 7.5) and with 0-12.5 % (w/v) NaCl (3.0 %). Chemotaxonomic analysis showed that the sole respiratory quinone of strain NH169-3 was ubiquinone 9; major fatty acids were C16 : 0 and C18 : 1ω9c, and major polar lipids were diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol and one unidentified glycolipid. The DNA G+C content was 52.7 mol%. The comparison of 16S rRNA gene sequences showed that strain NH169-3 was closely related to Marinobacter shengliensis SL013A34A2 with a similarity of 98.0 %. Three phylogenetic trees reconstructed with neighbour-joining, maximum-parsimony and maximum-likelihood methods using 16S rRNA gene sequences showed that strain NH169-3 was grouped into a separated branch with M. shengliensis SL013A34A2 in a clade of the genus Marinobacter and closely related to Marinobacter halophilus JCM 30472, Marinobacter vinifirmus DSM 17747 and Marinobacter hydrocarbonoclasticus DSM 8798. Analyses of both phenotypic and phylogenetic properties have suggested that strain NH169-3 was distinctive from species with validly published names in genus Marinobacter. Thus, strain NH169-3 (=MCCC 1K03455=KCTC 62226) is proposed as a novel species in genus Marinobacter with the name Marinobacter fuscus sp. nov.

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