Maribacter confluentis sp. nov., isolated from the junction between the ocean and a freshwater spring

Maribacter litoralis sp. nov. a marine bacterium isolated from seashore

A novel Gram-stain-negative, moderately halophilic and aerobic bacterium, designated strain SDRB-Phe2^T, was isolated from coastal sediment of the yellow sea in Sindu-ri, Republic of Korea. Cells were oxidase-positive, catalase-positive, rod-shaped and surrounded by a capsule with gliding motility. Colonies were yellow-coloured, circular, pulvinate with entire margins. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain SDRB-Phe2^T formed a distinct lineage within the genus Maribacter of the family Flavobacteriaceae. Stain SDRB-Phe2^T exhibited 16S rRNA gene sequence similarity values of 97.1-98.9 % to the type strains of Maribacterstanieri, Maribacterspongiicola, Maribacter forsetii, Maribacter dokdonensis, Maribacter aquivivus, Maribactercaenipelagi, Maribacterlitorisediminis, Maribactersedimenticola, Maribacterulvicola, Maribacter confluentis and Maribacter orientalis, and of 94.8-96.7 % to the type strains of the other species of the genus Maribacter. Strain SDRB-Phe2^T contained MK-6 as the predominant respiratory quinone and iso-C15 : 1 G, iso-C15 : 0 and summed feature 3 (C16 : 1ω7c and/or C16 : 1ω6c) as the major fatty acids. The polar lipids of strain SDRB-Phe2^T were phosphatidylethanolamine, one unidentified amino lipid and two unidentified lipids. The DNA G+C content was 36.2 mol%. DNA-DNA relatedness values of strain SDRB-Phe2^T to the type strains of the 11 phylogenetically related species of the genus Maribacter were 21.9-38.6 %. On the basis of the phenotypic features, phylogenetic and DNA-DNA hybridization analyses presented here, strain SDRB-Phe2^T (=JCM 32373^T=KCTC 62273^T=DSM 106042^T) represents a novel species of the genus Maribacter, for which the name Maribacterlitoralis sp. nov. is proposed.

Maribacter maritimus sp. nov., isolated from seawater

A novel Gram-stain-negative, motile by gliding and straight rod-shaped bacterial strain, designated HMF3635^T, was isolated from seawater of the East Sea, Republic of Korea. Strain HMF3635^T grew optimally on marine agar at 30 °C, pH 7.0-8.0 and 2.0 % NaCl. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain HMF3635^T belonged to the genus Maribacter and was most closely related to Maribacter arenosus CAU 1321^T (96.4 % sequence similarity) and Maribacter polysiphoniae KMM 6151^T (96.0 %). The major fatty acids were iso-C15 : 0, iso-C15 : 1 G and iso-C17 : 0 3-OH. The only respiratory quinone was menaquinone 6. The major polar lipids were phosphatidylethanolamine, four unidentified aminolipids, one unidentified phospholipid and three unidentified polar lipids. The DNA G+C content was 38.7 mol%. On the basis of the evidence presented in this study, strain HMF3635^T represents a novel species of the genus Maribacter, for which the name Maribacter maritimus sp. nov. is proposed. The type strain of the species is strain HMF3635^T (=KCTC 52399^T=NBRC 112671^T).

Maribacter pelagius sp. nov., isolated from seawater

A Gram-stain-negative, gliding, non-endospore-forming and slightly halophilic bacterial strain, CBA3204^T, was isolated from seawater and characterized by polyphasic taxonomic analysis. Phylogenetic analysis based on 16S rRNA sequences revealed that strain CBA3204^T formed a distinct lineage within the family Flavobacteriaceae. The 16S rRNA sequences of strain CBA3204^T had a sequence similarity level of 96.96 % to Maribacter arcticus KOPRI 20941^T as the nearest phylogenetic neighbour. The strain grew optimally at 25-30 °C and in the presence of 2-4 % (w/v) NaCl. The dominant menaquinone was MK-6 and the major fatty acids were iso-C15 : 0, iso-C17 : 0 3-OH and iso-C15 : 1 G. The DNA G+C content was 35.1 mol%. There were some differences in phenotypic properties among strain CBA3204^T and other Maribacter species. On the basis of polyphasic analysis containing phenotypic, phylogenetic and chemotaxonomic data, strain CBA3204^T (=KACC 17671^T=JCM 19533^T) is proposed as a novel species Maribacter pelagius sp. nov.

Aurantibacter crassamenti gen. nov., sp. nov., a bacterium isolated from marine sediment

A Gram-stain-negative, strictly aerobic, orange-colored, rod-shaped, chemoheterotrophic bacterium, designated HG732^T, was isolated from marine sediment in Japan. Phylogenetic analysis based on the 16S rRNA gene sequence indicated that the novel marine strain was affiliated with the family Flavobacteriaceae of the phylum Bacteroidetes and that it shared the highest (94.1 %) sequence similarity with Kriegella aquimaris KMM 3665^T. The strain could be differentiated phenotypically from related members of the family Flavobacteriaceae. Major fatty acids of strain HG732^T were iso-C15:1 G, iso-C15:0 and iso-C17:0 3-OH. The polar lipid profile consisted of phosphatidylglycerol, three unidentidied aminolipids and two unidentified lipids. The DNA G+C content of the strain was determined to be 35.2 mol%, and the major respiratory quinone was identified as menaquinone 6 (MK-6). From the distinct phylogenetic position and combination of genotypic and phenotypic characteristics, the strain is considered to represent a novel genus in the family Flavobacteriaceae, for which the name Aurantibacter crassamenti gen. nov., sp. nov. is proposed. The type strain of A. crassamenti gen. nov., sp. nov. is HG732^T (= KCTC 52207^T = NBRC 112211^T).

Maribacter arenosus sp. nov., isolated from marine sediment

A Gram-staining-negative, non-spore-forming, non-gliding, aerobic bacterial strain, designated CAU 1321T was isolated from marine sediment in Incheon, South Korea. The strain's taxonomic position was investigated using a polyphasic approach. CAU 1321T grew optimally at 30 °C and at pH 8 in the presence of 1 % (w/v) NaCl. Phylogenetic analysis based on the 16S rRNA gene sequence revealed that CAU 1321T represented a member of the genus Maribacter, closely related to Maribacter polysiphoniae KCTC 22021T (similarity 98.0 %). The strain contained MK-6 as the predominant menaquinone and iso-C15 : 0, iso-C17 : 0 3-OH, and iso-C15 : 1 G as the major fatty acids. The polar lipids of CAU 1321T consisted of phosphatidylethanolamine, one unidentified aminoglycolipid, five unidentified aminolipids, two unidentified aminophospholipids, two unidentified glycolipids and three unidentified lipids. The DNA G+C content was 40.6 mol% and the level of DNA-DNA relatedness between CAU 1321T and the most closely related strain, M. polysiphoniae KCTC 22021T was 25.2 %. On the basis of phenotypic and chemotaxonomic properties, and phylogenetic inference, CAU 1321T is considered to represent a novel species of the genus Maribacter, for which the name Maribacter arenosus sp. nov. is proposed. The type strain is CAU 1321T (=KCTC 52191T=NBRC 111990T).