Avrilella dinanensis gen. nov., sp. nov., a novel bacterium of the family Flavobacteriaceae isolated from human blood.

Polyphasic taxonomic analysis was performed on a novel bacterium, designated UR159T, isolated in 2016 from human blood of a septic patient hospitalized in France. Preliminary 16S rRNA gene sequence-based phylogenetic analysis indicated that strain UR159T belonged to the family Flavobacteriaceae, forming a distinct phyletic line distantly related (<94% sequence similarity) to known species of the family. Further phenotypic, chemotaxonomic and genomic analyses were performed. Cells were non-motile, oxidase-negative, catalase-positive Gram-negative rods. It was strictly aerobic yielding yellow-pigmented colonies, and was metabolically rather inert. Major fatty acids were iso-branched fatty acids, predominantly iso-C15:0 (55.5%) and iso-C17:1ω9c (8.8%). Whole genome sequencing revealed a 2.3-Mbp genome encoding a total of 2262 putative genes with a genomic DNA G+C content at 37.6mol%. The average nucleotide identity (ANI) and in silico DNA-DNA hybridization (isDDH) values between strain UR159T and the most closely related members of the Flavobacteriaceae family were <75% and <39%, respectively, much below the established cut-offs for ANI (<95-96%) and isDDH (<70%) for species and genus delineation. Average Amino Acid Identity (AAI) percentages were also estimated and were lower than 65% (cut-off proposed for genus delineation for uncultivated prokaryotes) in all cases, except for F. marinum that was just at the limit (65.1%). Based on these findings, we propose it as a new genus and species, Avrilella dinanensis gen. nov., sp. nov. (type strain UR159T=CIP 111616T=DSM 105483T).

Nonlabens xiamenensis sp. nov., isolated from coastal seawater.

A Gram-stain negative, rod-shaped and non-flagellated bacterium, designated strain 1Q3T, was isolated from coastal seawater in Xiamen Island, China, and subjected to taxonomic characterisation using a polyphasic approach. Strain 1Q3T was found to be aerobic, non-gliding and to lack flexirubin-type pigments. Catalase activity was found to be negative and oxidase positive. The strain has the ability to degrade protein. The nearly complete 16S rRNA gene sequence of strain 1Q3T shows high sequence similarities with Nonlabens aestuariivivens OITF-31T (96.1%), Nonlabens halophilus CAU 1131T and Nonlabens spongiae UST030701-156T (95.7% and 95.5%, respectively). Phylogenetic analysis based on 16S rRNA gene sequences and phylogenomic analysis based on a 92 bacterial core gene set indicated that strain 1Q3T should be affiliated to the genus Nonlabens, but forms a distinct monophyletic branch, which is separated from the other members within the genus Nonlabens. The predominant fatty acids (> 10%) were identified as iso-C17:0 3-OH, iso-C15:0 and anteiso-C15:0. The predominant respiratory quinone was found to be MK-6. The polar lipids were identified as phosphatidylethanolamine, a phospholipid, an aminolipid and three unidentified polar lipids. The draft genome size of strain 1Q3T is 3.7 Mb with genomic G + C content of 41.1 mol%. Based on these results, strain 1Q3T is concluded to represent a novel species within the genus Nonlabens, for which the name Nonlabens xiamenensis sp. nov. is proposed with the type strain 1Q3T (= MCCC 1A14023T = KCTC 62889T).

Genomic reconstructions and potential metabolic strategies of generalist and specialist heterotrophic bacteria associated with an estuary Synechococcus culture.

Interactions between photoautotrophs and heterotrophs are central to marine microbial ecosystems. Synechococcus are dominant marine phototrophs, and they are frequently associated with heterotrophic bacteria. These co-cultures provide a useful research system to investigate photoautotroph-heterotroph interactions in marine systems. Bacteria within the Roseobacter clade and Flavobacteria are two of the main bacterial lineages that exhibit intimate associations with Synechococcus populations. We conducted metagenomic analyses of a Synechococcus culture, followed by genomic binning of metagenomic contigs, and recovered five nearly complete genomes, including members of the Roseobacter clade (i.e. Marivita sp. XM-24) and Flavobacteria (i.e. Fluviicola sp. XM-24). Marivita sp. XM-24 is an ecological generalist of the Roseobacter clade and displays diverse metabolic capacities for the acquisition of nutrients and energy sources. Specifically, the genome contained numerous gene complements involved in the uptake and metabolism of nitrogen- and phosphorus-containing inorganic and organic compounds, in addition to the potential for aerobic anoxygenic photosynthesis, oxidation of carbon monoxide, inorganic sulfur oxidation, DMSP demethylation and PHA metabolism. The genome of the Flavobacteria representative, Fluviicola sp. XM-24, contained numerous peptidases, glycoside hydrolases, adhesion-related proteins and genes involved in gliding motility. Fluviicola sp. XM-24 likely specialize in the degradation of high molecular weight compound exudates from Synechococcus cells, including polysaccharides and polypeptides via attachment to particles, surfaces or cells. The distinct metabolic strategies identified within several heterotrophic bacteria that are associated with Syneochococcus cells provide insights into their lifestyles and nutrient utilization patterns, in addition to their interactions with photoautotrophs. Biological interactions, including mutualism, competition and antagonism, shape the microbial community structure of marine environments and are critical for understanding biogeochemical cycling in the ocean. These results provide valuable insights into the nature of interactions between dominant marine photoautotrophs and associated bacterial heterotrophs.

Zunongwangia flava sp. nov., belonging to the family Flavobacteriaceae, isolated from Salicornia europaea.

A yellow pigmented bacterium designated strain MBLN094T within the family Flavobacteriaceae was isolated from a halophyte Salicornia europaea on the coast of the Yellow Sea. This strain was a Gram-stain negative, aerobic, non-spore forming, rod-shaped bacterium. Phylogenetic analysis of the 16S rRNA gene sequence of strain MBLN094T was found to be related to the genus Zunongwangia, exhibiting 16S rRNA gene sequence similarity values of 97.0, 96.8, 96.4, and 96.3% to Zunongwangia mangrovi P2E16T, Z. profunda SM-A87T, Z. atlantica 22II14-10F7T, and Z. endophytica CPA58T, respectively. Strain MBLN094T grew at 20‒37°C (optimum, 25‒30°C), at pH 6.0‒10.0 (optimum, 7.0‒8.0), and with 0.5‒15.0% (w/v) NaCl (optimum, 2.0‒5.0%). Menaquinone MK-6 was the sole respiratory quinone. The polar lipids were phosphatidylethanolamine, two unidentified aminolipids, and four unidentified lipids. Major fatty acids were iso-C17:0 3-OH, summed feature 3 (C16:1ω6c and/or C16:1 ω7c), and iso-C15:0. The genomic DNA G + C content was 37.4 mol%. Based on these polyphasic taxonomic data, strain MBLN094T is considered to represent a novel species of the genus Zunongwangia, for which the name Zunongwangia flava sp. nov. is proposed. The type strain is MBLN094T (= KCTC 62279T = JCM 32262T).

Ascidiaceibacter salegens gen. nov., sp. nov., isolated from an ascidian.

An aerobic, Gram-stain negative, rod-shaped, non-motile bacterium, designated as strain HQA918T, was isolated from an ascidian, Botryllus schlosseri, which was collected from the coast of Weihai in the north of the Yellow Sea, in China. The strain grew optimally at 28-30 °C, at pH values 7.0-8.0, and in the presence of 1.0-3.0% (w/v) sodium chloride (NaCl). A phylogenetic analysis based on 16S rRNA gene sequences showed that strain HQA918T can be affiliated with the family Flavobacteriaceae in the phylum Bacteroidetes, with 92.7% similarity to its close relatives. The major fatty acids identified were iso-C15:0, iso-C15:0 3-OH, and summed feature 3 (iso-C15:0 2-OH and/or C16:1ω7c). The major polar lipids were phosphatidylethanolamine, one unidentified aminolipid, and five unidentified polar lipids. The G+C content of the genomic DNA was 44.1 mol%. On the basis of the phylogenetic, genotypic, phenotypic, and chemotaxonomic data, this organism should be classified as a representative of a novel genus, for which the name Ascidiaceibacter gen. nov. is proposed. The type species is Ascidiaceibacter salegens sp. nov. (type strain HQA918T = KCTC 52719T = MCCC 1K03259T).

CspB of an arctic bacterium, Polaribacter irgensii KOPRI 22228, confers extraordinary freeze-tolerance

ABSTRACT Freezing temperatures are a major challenge for life at the poles. Decreased membrane fluidity, uninvited secondary structure formation in nucleic acids, and protein cold-denaturation all occur at cold temperatures. Organisms adapted to polar regions possess distinct mechanisms that enable them to survive in extremely cold environments. Among the cold-induced proteins, cold shock protein (Csp) family proteins are the most prominent. A gene coding for a Csp-family protein, cspB, was cloned from an arctic bacterium, Polaribacter irgensii KOPRI 22228, and overexpression of cspB greatly increased the freeze-survival rates of Escherichia coli hosts, to a greater level than any previously reported Csp. It also suppressed the cold-sensitivity of an E. coli csp-quadruple deletion strain, BX04. Sequence analysis showed that this protein consists of a unique domain at its N-terminal end and a well conserved cold shock domain at its C-terminal end. The most common mechanism of Csp function in cold adaption is melting of the secondary structures in RNA and DNA molecules, thus facilitating transcription and translation at low temperatures. P. irgensii CspB bound to oligo(dT)-cellulose resins, suggesting single-stranded nucleic acid-binding activity. The unprecedented level of freeze-tolerance conferred by P. irgensii CspB suggests a crucial role for this protein in survival in polar environments.

Algoriella xinjiangensis gen. nov., sp. nov., a new psychrotolerant bacterium of the family Flavobacteriaceae.

An aerobic, Gram-stain negative, non-spore-forming and psychrotolerant bacterium, designated strain XJ109(T), was isolated from a sewage water sample collected from Xinjiang Uigur Autonomous Region, China. Phylogenetic analysis based on 16S rRNA gene sequence indicated that strain XJ109(T) represents a novel member of the family Flavobacteriaceae. The strain showed 95.5 % similarity with the 16S rRNA gene sequence of Empedobacter brevis LMG 4011(T), 95.4% with Chishuiella changwenlii BY4(T), 95.3% with Empedobacter falsenii NF 993(T) and 92.3% with Weeksella virosa DSM 16922(T). Strain XJ109(T) showed the common phenotypic and chemotaxonomic characteristics of the family Flavobacteriaceae, containing menaquinone-6 (MK-6) as the predominant respiratory quinone and iso-C17:0 3OH and iso-C15:0 as the major fatty acids. The polar lipid profile consisted of phosphatidylethanolamine, one unidentified phospholipid and two unidentified lipids. The genomic DNA G+C content was 38.0 mol%. Strain XJ109(T) was positive for catalase and oxidase activities, and it was observed to grow at 4-30 °C (optimal 16-20 °C), pH 6.5-10.0 (optimal 7.0-7.5) and in media containing 0-2.0% (w/v) NaCl (optimal 0.5 %). On the basis of the polyphasic evidence presented, strain XJ109(T) is considered to represent a novel genus and species of the family Flavobacteriaceae, for which the name Algoriella xinjiangensis gen. nov., sp. nov. is proposed. The type strain is XJ109(T) (=CGMCC 1.10229(T)=JCM 16590(T)).

Isolation and characterization of a novel marine Bacteroidetes as Algitalea ulvae gen. nov., sp. nov., isolated from the green alga Ulva pertusa.

A polyphasic taxonomic investigation was performed on a bacterial strain, 38-Ka-2(T), which was isolated from the green alga Ulva pertusa Kjellman (Chlorophyta) in Hokkaido, Japan. The bacterial cells were observed to be golden-yellow coloured, Gram-negative, strictly aerobic, non-spore-forming, non-motile and rod-shaped. Phylogenetic analyses based on the 16S rRNA gene sequence indicated that the new strain is a member of the family Flavobacteriaceae within the phylum Bacteroidetes and that it shows high sequence similarity (94.8 %) to Aquimarina addita JC2680(T). The genomic DNA G+C content of strain 38-Ka-2(T) was determined to be 36 mol%; MK-6 was identified as the major menaquinone; and the presence of iso-C15:0, C18:0 and iso-C17:0 3-OH as the major (>10 %) cellular fatty acids. The polar lipid profile was found to consist of phosphatidylethanolamine, an unidentified glycolipid and two unidentified lipids. From the distinct phylogenetic position and combination of genotypic and phenotypic characteristics, strain 38-Ka-2(T) is considered to represent a novel genus for which the name Algitalea ulvae gen. nov., sp. nov. is proposed. The type strain of A. ulvae is 38-Ka-2(T) (=KCTC 32994(T) = NBRC 110017(T)).

Proteorhodopsin from Dokdonia sp. PRO95 is a light-driven Na+-pump.

The gene encoding proteorhodopsin AEX55013 from Dokdonia sp. PRO95 was cloned and expressed in Escherichia coli cells. Illumination of the proteorhodopsin-producing E. coli cells in Na+-containing media resulted in alkalinization of the media. This response was accelerated by uncoupler CCCP and inhibited by penetrating anion SCN(-). Illumination of the cells in a sodium-free medium (made by substituting Na+ with K+) resulted in SCN(-)-stimulated and CCCP-sensitive acidification of the medium. Illumination of the proteorhodopsin-containing E. coli cells caused CCCP-resistant transmembrane sodium export from these cells. We conclude that the proteorhodopsin from the marine flavobacterium Dokdonia sp. PRO95 is a primary light-driven Na+-pump. A high level of the heterologous production in E. coli cells as well as stability and purity of the isolated protein makes this proteorhodopsin an attractive model for studying the mechanism of active sodium transmembrane translocation.

Eudoraea chungangensis sp. nov., isolated from an aquafarm waste water sludge.

A Gram-stain negative, non-spore-forming, non-motile, strictly aerobic bacterial strain, designated CAU 1296(T), was isolated from an aquafarm waste water sludge and its taxonomic position was investigated using a polyphasic approach. Cells of strain CAU 1296(T) grew optimally at 30 °C, at pH 7.5 and in the presence of 4 % (w/v) NaCl. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain CAU 1296(T) formed a distinct lineage within the genus Eudoraea and exhibited similarity to Eudoraea adriatica AS06/20a(T) (95.4 % similarity). The major cellular fatty acids of the isolate were iso-C15:0, iso-C15:1 G, and summed feature 3 (C16:1 ω6c and C16:1 ω7c). The polar lipid pattern of strain CAU 1296(T) consisted of phosphatidylethanolamine, and unidentified lipids including a phosphoglycolipid, phospholipid, glycolipid, aminophospholipid, two aminolipids, and six further unidentified lipids. The strain contained menaquinone-6 (MK-6) as the major isoprenoid quinone. The G+C content of the genomic DNA was 38.7 mol%. On the basis of phenotypic, chemotaxonomic, and phylogenetic data, strain CAU 1296(T) should be classified as a novel species in the genus Eudoraea, for which the name Eudoraea chungangensis sp. nov. is proposed. The type strain is CAU 1296(T) (=KCTC 42048(T), =CCUG 66239(T), =CECT 8744(T)).

Description of Lacinutrix venerupis sp. nov.: a novel bacterium associated with reared clams.

A group of five Gram-negative strains isolated from clams (Venerupis decussata and Venerupis philippinarum) in Galicia (NW Spain) were analyzed using a polyphasic taxonomic approach. The strains were non-motile, strictly aerobic rods, and formed yellow-pigmented colonies. Based on 16S rRNA gene sequence similarity, the clam isolates belonged to the Lacinutrix genus, within the Flavobacteriaceae family, and showed the highest sequence similarities with Lacinutrix mariniflava (97.0%) and Lacinutrix algicola (96.9%). The DNA G+C content of the designated type strain Cmf 20.8(T) was 34.1%, which was within the range of the other species in the genus (29.0-37.0%). The main cellular fatty acids of the type strain Cmf 20.8(T) were iso-C15:0 3-OH, iso-C15:1 G, iso-C15:0 and iso-C17:0 3-OH. The DNA-DNA analysis value of strain Cmf 20.8(T) with L. mariniflava AKS292(T) was 51% and with L. algicola AKS293(T) it was 56%. Phenotypic data showed that the isolates could be differentiated easily from the other species of the genus. On the basis of these results, the strains represent a novel species of the genus Lacinutrix, for which the name Lacinutrix venerupis sp. nov. is proposed, with Cmf 20.8(T) (=CECT 8573(T)=DSM 28755(T)) as the designated type strain.

Polaribacter marinivivus sp. nov., a member of the family Flavobacteriaceae isolated from seawater.

A Gram-stain negative, non-flagellated, non-gliding, aerobic and rod-shaped bacterium, designated GYSW-15(T), was isolated from a seawater of Geoje island on the South Sea, South Korea, and subjected to a polyphasic taxonomic approach. Strain GYSW-15(T) was found to grow optimally at 30 °C, at pH 7.0-8.0 and in the presence of approximately 2.0 % (w/v) NaCl. Neighbour-joining phylogenetic tree based on 16S rRNA gene sequences showed that strain GYSW-15(T) belongs to the genus Polaribacter, clustering coherently with the type strain of Polaribacter porphyrae showing sequence similarity value of 97.0 %. Strain GYSW-15(T) exhibited 16S rRNA gene sequence similarity values of 94.3-96.4 % to the type strains of the other Polaribacter species. Strain GYSW-15(T) was found to contain MK-6 as the predominant menaquinone and iso-C15:0, iso-C15:1 G, iso-C16:0 3-OH and summed feature 3 (C16:1 ω7c and/or C16:1 ω6c) as the major fatty acids. The polar lipid profile of strain GYSW-15(T) containing phosphatidylethanolamine and an unidentified lipid as major components was similar to that of the type strain of P. porphyrae. The DNA G + C content of strain GYSW-15(T) was determined to be 31.2 mol% and its mean DNA-DNA relatedness with P. porphyrae LMG 26671(T) was 17 %. Differential phenotypic properties, together with its phylogenetic and genetic distinctiveness, revealed that strain GYSW-15(T) is separated from recognized Polaribacter species. On the basis of the data presented, strain GYSW-15(T) is considered to represent a novel species of the genus Polaribacter, for which the name Polaribacter marinivivus sp. nov. is proposed. The type strain is GYSW-15(T) ( = KCTC 42156(T) = CECT 8655(T)).

Lacinutrix jangbogonensis sp. nov., a psychrophilic bacterium isolated from Antarctic marine sediment and emended description of the genus Lacinutrix.

A Gram-negative, strictly aerobic, non-motile, rod-shaped and psychrophilic bacterial strain, PAMC 27137(T), was isolated from the marine sediment of the Ross Sea, Antarctica. Strain PAMC 27137(T) was observed to grow at 4-10 °C, at pH 6.5-7.5 and in the presence of 2.5-4.0 % (w/v) sea salts. Phylogenetic analysis based on the 16S rRNA gene sequence indicated that strain PAMC 27137(T) belongs to the genus Lacinutrix showing the high similarities with Lacinutrix mariniflava JCM 13824(T) (97.6 %) and Lacinutrix algicola JCM 13825(T) (97.1 %). Genomic relatedness analyses based on the average nucleotide identity and the genome-to-genome distance showed that strain PAMC 27137(T) is clearly distinguished from the most closely related Lacinutrix species. The major fatty acids (>5 %) were identified as iso-C15:1 G (19.9 %), iso-C15:0 (19.3 %), iso-C17:0 3-OH (11.3 %), summed feature 9 (C16:0 10-methyl and/or iso-C17:1 ω9c as defined by MIDI, 9.1 %), iso-C15:0 3-OH (7.5 %), and anteiso-C15:1 A (5.8 %). The polar lipids were found to consist of phosphatidylethanolamine, an unidentified aminolipid, an unidentified aminophospholipid, and five unidentified phospholipids. The major respiratory quinone was identified as MK-6. The genomic DNA G+C content was determined to be 32.1 mol%. Based on the data from this polyphasic taxonomic study, strain PAMC 27137(T) is considered to represent a novel species of the genus Lacinutrix, for which the name Lacinutrix jangbogonensis sp. nov. is proposed. The type strain is PAMC 27137(T) (=KCTC 32573(T)=JCM 19883(T)).

Flavimarina pacifica gen. nov., sp. nov., a new marine bacterium of the family Flavobacteriaceae, and emended descriptions of the genus Leeuwenhoekiella, Leeuwenhoekiella aequorea and Leeuwenhoekiella marinoflava.

A facultatively anaerobic, Gram-stain negative, rod-shaped and yellow pigmented bacterium, designated strain IDSW-73(T), was isolated from a seawater sample and subjected to a polyphasic taxonomic study. Phylogenetic analysis based on 16S rRNA gene sequences revealed that the novel strain formed a distinct phyletic line in the family Flavobacteriaceae and is most closely related to the members of the genus Leeuwenhoekiella, with 16S rRNA gene sequence similarity of 91.4-92.6 %. Strain IDSW-73(T) was found to be able to grow with 0-12 % NaCl and at 4-33 °C; and was able to hydrolyse gelatin, starch and Tweens 20, 40 and 80. The DNA G+C content was determined to be 42.2 mol%. The predominant cellular fatty acids were identified as branched-chain saturated and unsaturated and straight-chain unsaturated fatty acids such as iso-C15:0, iso-C15:1, iso-C17:1 ω9c, C15:1 ω6c, iso-C15:0 3-OH, iso-C17:0 3-OH and summed feature 3 (as defined by MIDI), comprising iso-C15:0 2-OH and/or C16:1 ω7c. The polar lipids found were phosphatidylethanolamine, two unknown aminolipids and one unknown lipid. The major respiratory quinone was identified as MK-6. The significant molecular distinctiveness between the novel isolate and its nearest neighbours were strongly supported by notable differences in physiological and biochemical tests. Therefore, strain IDSW-73(T) is considered to represent a novel genus and species within the family Flavobacteriaceae, for which the name Flavimarina pacifica gen. nov., sp. nov. is proposed. The type strain is IDSW-73(T) (=KCTC 32466(T) = KMM 6759(T)). Emended descriptions of the recognized species of the genus Leeuwenhoekiella are also proposed.

Sabulilitoribacter multivorans gen. nov., sp. nov., a polysaccharide-degrading bacterium of the family Flavobacteriaceae isolated from seashore sand.

A Gram-negative, aerobic, non-flagellated, non-gliding and rod-shaped bacterial strain, designated M-M16(T), was isolated from seashore sand around a seaweed farm on the South Sea, South Korea, and its taxonomic position was investigated by using a polyphasic study. Strain M-M16(T) grew optimally at 30 °C, at pH 7.0-8.0 and in the presence of 2 % (w/v) NaCl. Strain M-M16(T) exhibited the highest 16S rRNA gene sequence similarity values to the type strains of Gaetbulibacter lutimaris (96.5 %) and Flaviramulus basaltis (95.8 %). Neighbour-joining and maximum-parsimony phylogenetic trees based on 16S rRNA gene sequences revealed that strain M-M16(T) clustered with the type strains of Gaetbulibacter species and F. basaltis. Strain M-M16(T) contained MK-6 as the predominant menaquinone and iso-C15:1 G, iso-C15:0 and iso-C17:0 3-OH as the major fatty acids. The major polar lipids detected in strain M-M16(T) were phosphatidylethanolamine and one unidentified lipid. The DNA G+C content of strain M-M16(T) was 37.4 mol%. The phylogenetic and chemotaxonomic data and other phenotypic properties revealed that strain M-M16(T) represents a novel genus and species within the family Flavobacteriaceae, for which the name Sabulilitoribacter multivorans gen. nov., sp. nov. is proposed. The type strain of S. multivorans is M-M16(T) (= KCTC 32326(T) = CCUG 63831(T)).

Nonlabens arenilitoris sp. nov., a member of the family Flavobacteriaceae isolated from seashore sand.

A Gram-staining-negative, non-spore-forming, aerobic, non-flagellated, non-gliding and rod-shaped bacterial strain, designated M-M3(T), was isolated from marine sand on the southern coast of South Korea and subjected to a polyphasic study. Strain M-M3(T) was observed to grow optimally at 25-30 °C, at pH 7.0-8.0 and in the presence of 2 % (w/v) NaCl. Phylogenetic trees based on 16S rRNA gene sequences revealed that strain M-M3(T) fell within the clade comprising Nonlabens species, joining the type strain of Nonlabens ulvanivorans, with which it exhibited the highest 16S rRNA gene sequence similarity value of 99.4 %. Sequence similarity to the type strains of the other Nonlabens species was 93.0-95.2 % and <92.2 % to those of other species used in the phylogenetic analysis. Strain M-M3(T) was found to contain MK-6 as the predominant menaquinone and iso-C15:0 and iso-C17:0 3-OH as the major fatty acids. The major polar lipids were determined to be phosphatidylethanolamine, five unidentified lipids and one unidentified aminolipid. The DNA G+C content of strain M-M3(T) was determined to be 38.2 mol% and its DNA-DNA relatedness values with N. ulvanivorans DSM 22727(T) was 42 ± 6.2 %. Differential phenotypic properties, together with the phylogenetic and genetic distinctiveness, revealed that strain M-M3(T) is separate from other Nonlabens species. On the basis of the data presented, strain M-M3(T) is considered to represent a novel species of the genus Nonlabens, for which the name Nonlabens arenilitoris sp. nov. is proposed. The type strain is M-M3(T) (=KCTC 32109(T) = CCUG 62919(T)).

Nonlabens marinus [corrected] sp. nov., a novel member of the Flavobacteriaceae isolated from the Pacific Ocean.

Two aerobic, Gram-negative, orange pigmented and irregular rod-shaped bacteria, designated S1-05 and S1-08(T), were isolated from seawater from the Pacific Ocean. Phylogenetic analysis based on their 16S rRNA gene sequences revealed that the novel isolates could be affiliated with the genus Nonlabens of the family Flavobacteriaceae. The strains S1-05 and S1-08(T) shared 100 % pairwise sequences similarity with each other and showed less than 96.8 % similarity with the cultivated members of the genus Nonlabens. The novel isolates are phenotypically and physiologically different from strains described previously. The strains were found to be non-motile, oxidase positive, catalase positive and hydrolyzed gelatin and aesculin. The G+C contents of the DNA were determined to 41.4 and 41.7 mol% and MK-6 the predominant menaquinone. Anteiso-C15:0 and iso-C15:0 were found to be the major two cellular fatty acids. On the basis of polyphasic taxonomic studies, it was concluded that strains S1-05 and S1-08(T) represent a novel species within the genus Nonlabens, for which the name Nonlabens marina sp. nov. is proposed. The type strain of N. marina is S1-08(T) (=KCTC 23432(T) = NBRC 107738(T)).

Unification of the genera Nonlabens, Persicivirga, Sandarakinotalea and Stenothermobacter into a single emended genus, Nonlabens, and description of Nonlabens agnitus sp. nov.

Phylogenetic analyses based on 16S rRNA gene sequences showed that a bacterial isolate, designated JC2678(T), represents a distinct phyletic line within the suprageneric monophyletic clade containing the genera Nonlabens, Persicivirga, Stenothermobacter and Sandarakinotalea. The polyphasic data presented in this study demonstrated that the members belonging to the Nonlabens-like clade overall constitute a single genus. Therefore, it is proposed to transfer the members of genera Persicivirga O'Sullivan et al. 2006, Stenothermobacter Lau et al. 2006 and Sandarakinotalea Khan et al. 2006 to the genus Nonlabens Lau et al. 2005. Thus, P. dokdonensis (Yoon et al. 2006) Nedashkovskaya et al. 2009, P. ulvanivorans Barbeyron et al. 2010, P. xylanidelens O'Sullivan et al. 2006, Sandarakinotalea sediminis Khan et al. 2006 and Stenothermobacter spongiae Lau et al. 2006 should be transferred to Nonlabens dokdonensis comb. nov., Nonlabens ulvanivorans comb. nov., Nonlabens xylanidelens comb. nov., Nonlabens sediminis comb. nov. and Nonlabens spongiae comb. nov., respectively. In addition, strain JC2678(T) (=KACC 14155(T)=JCM 17109(T)) is proposed to constitute a novel species belonging to the genus Nonlabens with the name of Nonlabens agnitus sp. nov.

Muricauda beolgyonensis sp. nov., isolated from a tidal flat.

The taxonomic position of a Gram-staining-negative, non-motile, rod-shaped bacterium, strain BB-My12(T), which was isolated from a sediment sample collected from a tidal flat in Korea, was investigated by using a polyphasic approach. Strain BB-My12(T) grew optimally at 37 °C, at pH 7.0-7.5 and in the presence of 2-3 % (w/v) NaCl. In phylogenetic analyses based on 16S rRNA gene sequences, strain BB-My12(T) fell within the cluster comprising species of the genus Muricauda and appeared most similar to the type strains of Muricauda aquimarina, Muricauda lutimaris and Muricauda ruestringensis (97.5-97.6 % sequence similarity). The DNA G+C content was 45.0 mol%. Strain BB-My12(T) contained MK-6 as the predominant menaquinone and iso-C(15 : 1), iso-C(17 : 0) 3-OH and iso-C(15 : 0) as the major cellular fatty acids. The polar lipids of strain BB-My12(T) were phosphatidylethanolamine and four unidentified lipids. The DNA-DNA relatedness values between strain BB-My12(T) and the type strains of the three species of the genus Muricauda that appeared most closely related were in the range 5-7 %. The genetic distinctiveness and some phenotypic properties indicated that strain BB-My12(T) did not belong to any established species of the genus Muricauda. Strain BB-My12(T) is therefore considered to represent a novel species of the genus Muricauda, for which the name Muricauda beolgyonensis sp. nov. is proposed. The type strain is BB-My12(T) ( = KCTC 23501(T)  = CCUG 60800(T)).

Postechiella marina gen. nov., sp. nov., isolated from seawater.

A Gram-staining-negative, strictly aerobic, non-motile, yellow-pigmented bacterium, designated strain M091(T), was isolated from seawater at Damupo beach in Pohang, Republic of Korea, and investigated using a polyphasic taxonomic approach. The novel strain grew optimally at 25 °C, pH 7.0-8.0, and in the presence of 3% (w/v) NaCl. In a phylogenetic analysis based on 16S rRNA gene sequences, strain M091(T) formed a lineage within the family Flavobacteriaceae that was distinct from the most closely related genera of Flaviramulus (95.1% sequence similarity), Algibacter (94.9-93.9%), Mariniflexile (94.8-94.2%), Winogradskyella (94.8-93.2%), Lacinutrix (94.7-93.8%) and Tamlana (94.7-92.9%). The polar lipid profile of the novel strain comprised phosphatidylethanolamine, two unidentified aminolipids, one unidentified phospholipid and seven unidentified lipids. The predominant cellular fatty acids were iso-C(15:0) (20.5%), iso-C(17:0) 3-OH (15.4%), iso-C(15:0) 3-OH (12.4%), C(15:0) (10.9%) and iso-C(15:1) G (9.9%). The genomic DNA G+C content of strain M091(T) was 34.4 mol% and the major respiratory quinone was MK-6. Based on phenotypic and genotypic data, strain M091(T) represents a new genus and novel species in the family Flavobacteriaceae, for which the name Postechiella marina gen. nov., sp. nov. is proposed. The type strain of the type species is M091(T) (=KCTC 23537(T)=JCM 17630(T)).