Croceicoccus ponticola sp. nov., a lipolytic bacterium isolated from seawater.

A lipolytic, Gram-stain-negative, aerobic, non-motile and coccoid, ovoid or rod-shaped bacterial strain, designated GM-16T, was isolated from seawater around Pohang in the Republic of Korea. Strain GM-16T grew optimally at 30 °C and in the presence of 1.0-2.0 % (w/v) NaCl. The neighbour-joining phylogenetic tree of 16S rRNA gene sequences showed that strain GM-16T fell within the clade comprising the type strains of Croceicoccus species. Strain GM-16T exhibited the highest 16S rRNA gene sequence similarity (97.7 %) to the type strain of Croceicoccus pelagius and sequence similarities of 96.3-96.7 % to the type strains of the other Croceicoccus species. Strain GM-16T contained Q-10 as the predominant ubiquinone and C18 : 1ω7c and summed feature 3 (C16 : 1ω7c and/or C16 : 1ω6c) as major fatty acids. The major polar lipids of strain GM-16T were phosphatidylcholine, phosphatidylethanolamine, phosphatidylglycerol, sphingoglycolipid and one unidentified glycolipid. The DNA G+C content of strain GM-16T was 62.6 mol%. The mean DNA-DNA relatedness value between strain GM-16T and C. pelagius DSM 101479T was 16 %. The average nucleotide identity values between strain GM-16T and the type strains of C.roceicoccus pelagius, C.roceicoccus marinus, C.roceicoccus naphthovorans and C.roceicoccus mobilis were 83.96-84.44 %. The phylogenetic and genetic data and differential phenotypic properties indicated that strain GM-16T is separated from recognized Croceicoccus species. On the basis of the data presented here, strain GM-16T is considered to represent a novel species of the genus Croceicoccus, for which the name Croceicoccus ponticola sp. nov. is proposed. The type strain is GM-16T (=KACC 19611T=KCTC 62423T=NBRC 113192T).

Altererythrobacter insulae sp. nov., a lipolytic bacterium isolated from a tidal flat.

A lipolytic, Gram-stain-negative, aerobic, non-motile and coccoid, ovoid or rod-shaped bacterial strain, designated BPTF-M16T, was isolated from tidal flat sediment on the Yellow Sea in the Republic of Korea. Strain BPTF-M16T grew optimally at 30 °C and in the presence of 2.0-3.0 % (w/v) NaCl. A phylogenetic tree of 16S rRNA gene sequences showed that strain BPTF-M16T fell within the clade comprising the type strains of Altererythrobacter species. Strain BPTF-M16T exhibited 16S rRNA gene sequence similarity values of 98.0 and 97.1 % to the type strains of Altererythrobacterishigakiensis and Altererythrobactermarinus, respectively, and of less than 97.0 % to the type strains of the other recognized species. Strain BPTF-M16T contained Q-10 as the predominant ubiquinone and C18 : 1ω7c as the major fatty acid. The major polar lipids detected in strain BPTF-M16T were phosphatidylcholine, phosphatidylethanolamine, phosphatidylglycerol, sphingoglycolipid and one unidentified glycolipid. Mean DNA-DNA relatedness values of strain BPTF-M16T with the type strains of A. ishigakiensis and A. marinus were 22 and 13 %, respectively. The average nucleotide identity value between strain BPTF-M16T and the type strain of A. ishigakiensis was 76.80 %. Differential phenotypic properties, together with the phylogenetic and genetic data, revealed that strain BPTF-M16T is separated from recognized Altererythrobacter species. On the basis of the data presented here, strain BPTF-M16T is considered to represent a novel species of the genus Altererythrobacter, for which the name Altererythrobacter insulae sp. nov. is proposed. The type strain is BPTF-M16T (=KCTC 62421T=KACC 19609T=NBRC 113190T).

Kaposi's Sarcoma-Associated Herpesvirus Viral Interferon Regulatory Factor 4 (vIRF4) Perturbs the G1-S Cell Cycle Progression via Deregulation of the cyclin D1 Gene.

Kaposi's sarcoma-associated herpesvirus (KSHV) infection modulates the host cell cycle to create an environment optimal for its viral-DNA replication during the lytic life cycle. We report here that KSHV vIRF4 targets the ß-catenin/CBP cofactor and blocks its occupancy on the cyclin D1 promoter, suppressing the G1-S cell cycle progression and enhancing KSHV replication. This shows that KSHV vIRF4 suppresses host G1-S transition, possibly providing an intracellular milieu favorable for its replication.

Shiga Toxins Activate the NLRP3 Inflammasome Pathway To Promote Both Production of the Proinflammatory Cytokine Interleukin-1ß and Apoptotic Cell Death.

Shiga toxin (Stx)-mediated immune responses, including the production of the proinflammatory cytokines tumor necrosis-α (TNF-α) and interleukin-1ß (IL-1ß), may exacerbate vascular damage and accelerate lethality. However, the immune signaling pathway activated in response to Stx is not well understood. Here, we demonstrate that enzymatically active Stx, which leads to ribotoxic stress, triggers NLRP3 inflammasome-dependent caspase-1 activation and IL-1ß secretion in differentiated macrophage-like THP-1 (D-THP-1) cells. The treatment of cells with a chemical inhibitor of glycosphingolipid biosynthesis, which suppresses the expression of the Stx receptor globotriaosylceramide and subsequent endocytosis of the toxin, substantially blocked activation of the NLRP3 inflammasome and processing of caspase-1 and IL-1ß. Processing and release of both caspase-1 and IL-1ß were significantly reduced or abolished in Stx-intoxicated D-THP-1 cells in which the expression of NLRP3 or ASC was stably knocked down. Furthermore, Stx mediated the activation of caspases involved in apoptosis in an NLRP3- or ASC-dependent manner. In Stx-intoxicated cells, the NLRP3 inflammasome triggered the activation of caspase-8/3, leading to the initiation of apoptosis, in addition to caspase-1-dependent pyroptotic cell death. Taken together, these results suggest that Stxs trigger the NLRP3 inflammasome pathway to release proinflammatory IL-1ß as well as to promote apoptotic cell death.

The structural basis for the negative regulation of thioredoxin by thioredoxin-interacting protein.

The redox-dependent inhibition of thioredoxin (TRX) by thioredoxin-interacting protein (TXNIP) plays a pivotal role in various cancers and metabolic syndromes. However, the molecular mechanism of this regulation is largely unknown. Here, we present the crystal structure of the TRX-TXNIP complex and demonstrate that the inhibition of TRX by TXNIP is mediated by an intermolecular disulphide interaction resulting from a novel disulphide bond-switching mechanism. Upon binding to TRX, TXNIP undergoes a structural rearrangement that involves switching of a head-to-tail interprotomer Cys63-Cys247 disulphide between TXNIP molecules to an interdomain Cys63-Cys190 disulphide, and the formation of a de novo intermolecular TXNIP Cys247-TRX Cys32 disulphide. This disulphide-switching event unexpectedly results in a domain arrangement of TXNIP that is entirely different from those of other arrestin family proteins. We further show that the intermolecular disulphide bond between TRX and TXNIP dissociates in the presence of high concentrations of reactive oxygen species. This study provides insight into TRX and TXNIP-dependent cellular regulation.

Gaetbulibacter lutimaris sp. nov., isolated from a tidal flat sediment.

A Gram-stain-negative, aerobic, non-flagellated, non-gliding, rod-shaped bacterial strain, D1-y4(T), was isolated from a tidal flat sediment of the South Sea in South Korea and subjected to a polyphasic study. Strain D1-y4(T) grew optimally at 25 °C, at pH 7.0-7.5 and in the presence of 2-3 % (w/v) NaCl. Phylogenetic trees based on 16S rRNA gene sequences revealed that strain D1-y4(T) belonged to the genus Gaetbulibacter, joining the type strain of Gaetbulibacter marinus, with which it exhibited 97.8 % similarity. Sequence similarities to Gaetbulibacter saemankumensis SMK-12(T) and Gaetbulibacter aestuarii KYW382(T) were 96.5 and 96.2 %, respectively. Strain D1-y4(T) contained MK-6 as the predominant menaquionone and iso-C15 : 0, iso-C15 : 1 G and anteiso-C15 : 0 as the major fatty acids. The major polar lipids were phosphatidylethanolamine and one unidentified lipid. The DNA G+C content of strain D1-y4(T) was 34.6 mol% and its mean DNA-DNA relatedness value with G. marinus KCTC 23046(T) was 7 %. The phylogenetic and genetic distinctiveness and differential phenotypic properties revealed that strain D1-y4(T) is distinguishable from the three recognized Gaetbulibacter species. On the basis of the data presented here, strain D1-y4(T) is considered to represent a novel species of the genus Gaetbulibacter, for which the name Gaetbulibacter lutimaris sp. nov. is proposed. The type strain is D1-y4(T) ( = KCTC 23716(T)  = CCUG 61504(T)).

Construction and manipulation of a new Kaposi's sarcoma-associated herpesvirus bacterial artificial chromosome clone.

Efficient genetic modification of herpesviruses such as Kaposi's sarcoma-associated herpesvirus (KSHV) has come to rely on bacterial artificial chromosome (BAC) technology. In order to facilitate this approach, we generated a new KSHV BAC clone, called BAC16, derived from the rKSHV.219 virus, which stems from KSHV and Epstein-Barr virus-coinfected JSC1 primary effusion lymphoma (PEL) cells. Restriction enzyme and complete sequencing data demonstrate that the KSHV of JSC1 PEL cells showed a minimal level of sequence variation across the entire viral genome compared to the complete genomic sequence of other KSHV strains. BAC16 not only stably propagated in both Escherichia coli and mammalian cells without apparent genetic rearrangements, but also was capable of robustly producing infectious virions (∼5 × 10(7)/ml). We also demonstrated the utility of BAC16 by generating deletion mutants of either the K3 or K5 genes, whose products are E3 ligases of the membrane-associated RING-CH (MARCH) family. While previous studies have shown that individual expression of either K3 or K5 results in efficient downregulation of the surface expression of major histocompatibility complex class I (MHC-I) molecules, we found that K5, but not K3, was the primary factor critical for the downregulation of MHC-I surface expression during KSHV lytic reactivation or following de novo infection. The data presented here demonstrate the utility of BAC16 for the generation and characterization of KSHV knockout and mutant recombinants and further emphasize the importance of functional analysis of viral genes in the context of the KSHV genome besides the study of individual gene expression.

Mucilaginibacter litoreus sp. nov., isolated from marine sand.

A Gram-staining-negative, non-spore-forming, facultatively anaerobic, non-flagellated, non-gliding, rod-shaped bacterium, designated strain BR-18(T), was isolated from marine sand collected on the western coast of South Korea. The taxonomic position of the novel strain was determined using a polyphasic approach. Strain BR-18(T) grew optimally at 25 °C, at pH 6.5-7.0 and in the absence of NaCl. In phylogenetic analyses based on 16S rRNA gene sequences, the novel strain fell within a clade comprising members of the genus Mucilaginibacter and appeared most closely related to Mucilaginibacter lutimaris BR-3(T) (96.6 % sequence similarity) and Mucilaginibacter rigui WPCB133(T) (95.9 %). The novel strain showed lower levels of 16S rRNA gene sequence similarity with the type strains of other members of the genus Mucilaginibacter (93.4-95.5 %) and those of other species included in the phylogenetic analyses (<91.6 %). Strain BR-18(T) contained MK-7 as its predominant menaquinone, summed feature 3 (C(16 : 1)ω7c and/or iso-C(15 : 0) 2-OH) and iso-C(15 : 0) as its major fatty acids, phosphatidylethanolamine and an unidentified aminophospholipid as its major polar lipids, and sphingolipids. The genomic DNA G+C content of the novel strain was 42.4 mol%. Based on the phylogenetic and phenotypic data, strain BR-18(T) represents a novel species of the genus Mucilaginibacter, for which the name Mucilaginibacter litoreus sp. nov. is proposed. The type strain is BR-18(T) ( = KCTC 23697(T)  = CCUG 61484(T)).

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)).

Thalassobius maritimus sp. nov., isolated from seawater.

A Gram-stain-negative, aerobic, motile, rod-shaped bacterial strain, GSW-M6(T), was isolated from seawater of Geoje island, Korea, and was subjected to a polyphasic taxonomic study. Strain GSW-M6(T) grew optimally at pH 7.0-8.0, at 30 °C and in the presence of 2% (w/v) NaCl. In the neighbour-joining phylogenetic tree based on 16S rRNA gene sequences, strain GSW-M6(T) clustered with Thalassobius aestuarii, Thalassobius gelatinovorus and Thalassobius mediterraneus. Strain GSW-M6(T) exhibited 96.2-96.9% 16S rRNA gene sequence similarity to the type strains of these three Thalassobius species. Strain GSW-M6(T) contained Q-10 as the predominant ubiquinone and C(18:1)ω7c as the major fatty acid. The polar lipid profiles of strain GSW-M6(T) and the type strains of the three Thalassobius species were similar, with phosphatidylcholine, phosphatidylglycerol, phosphatidylethanolamine and an unidentified lipid as common major components. The DNA G+C content of strain GSW-M6(T) was 57 mol%. The mean level of DNA-DNA relatedness between strain GSW-M6(T) and the type strain of Thalassobius gelatinovorus was 17%. Differential phenotypic properties, together with the phylogenetic and genetic distinctiveness, enabled strain GSW-M6(T) to be differentiated from recognized species of the genus Thalassobius. On the basis of the data presented, strain GSW-M6(T) is considered to represent a novel species of the genus Thalassobius, for which the name Thalassobius maritimus sp. nov. is proposed. The type strain is GSW-M6(T) (=KCTC 23347(T) =CCUG 60021(T)).

Algoriphagus namhaensis sp. nov., isolated from seawater.

A Gram-staining-negative, non-motile, non-spore-forming bacterial strain, DPG-3(T), was isolated from seawater from the South Sea in Korea, and its taxonomic position was investigated using a polyphasic approach. Strain DPG-3(T) grew optimally at 30 °C and in the presence of 2% (w/v) NaCl. In a neighbour-joining phylogenetic tree based on 16S rRNA gene sequences, strain DPG-3(T) fell within a clade comprising Algoriphagus species and appeared most closely related to Algoriphagus halophilus JC 2051(T) (96.1%16S rRNA gene sequence similarity) and Algoriphagus lutimaris S1-3(T) (96.4%). The type strains of other Algoriphagus species showed 16S rRNA gene sequence similarities of 92.9-96.0% with strain DPG-3(T). The predominant menaquinone of strain DPG-3(T) was MK-7. The major fatty acids were iso-C(15:0) and iso-C(15:0) 2-OH and/or C(16:1)ω7c (summed feature 3). The major polar lipids detected in strain DPG-3(T) were phosphatidylcholine, phosphatidylethanolamine and an unidentified lipid. The genomic DNA G+C content was 44.8 mol%. On the basis of phenotypic, chemotaxonomic and phylogenetic data, strain DPG-3(T) is considered to represent a novel species of the genus Algoriphagus, for which the name Algoriphagus namhaensis sp. nov. is proposed. The type strain is DPG-3(T) (=KCTC 23419(T)=CCUG 60523(T)).

Mucilaginibacter lutimaris sp. nov., isolated from a tidal flat sediment.

A Gram-staining-negative, non-spore-forming, facultatively aerobic, non-motile, rod-shaped bacterial strain, BR-3(T), was isolated from a tidal flat on the western coast of Korea, and subjected to a polyphasic study. Strain BR-3(T) grew optimally at 25 °C, at pH 6.5-7.0 and in the absence of NaCl. Phylogenetic analyses based on 16S rRNA gene sequences revealed that strain BR-3(T) fell within the clade comprising species of the genus Mucilaginibacter, joining the type strain of Mucilaginibacter rigui, with which it exhibited highest 16S rRNA gene sequence similarity (98.2%). 16S rRNA gene sequence similarity values between strain BR-3(T) and the type strains of the other species of the genus Mucilaginibacter were in the range 93.8-95.9%. A mean DNA-DNA relatedness value between strain BR-3(T) and M. rigui KCTC 12534(T) was 21%. Strain BR-3(T) contained MK-7 as the predominant menaquinone and C(16:1)ω7c and/or iso-C(15:0) 2-OH and iso-C(15:0) as the major fatty acids. The major polar lipids were phosphatidylethanolamine and an unidentified aminophospholipid. The DNA G+C content was 49.8 mol%. Differential phenotypic properties and phylogenetic and genetic distinctiveness of strain BR-3(T) demonstrated that this strain is separate from M. rigui as well as the other species of the genus Mucilaginibacter. On the basis of the data presented, strain BR-3(T) is considered to represent a novel species of the genus Mucilaginibacter, for which the name Mucilaginibacter lutimaris sp. nov. is proposed. The type strain is BR-3(T) (=KCTC 23461(T) =CCUG 60742(T)).

Tropicimonas aquimaris sp. nov., isolated from seawater, and emended description of the genus Tropicimonas Harwati et al. 2009.

A Gram-staining-negative, aerobic, non-motile and rod-shaped bacterial strain, designated DPG-21(T), was isolated from seawater from the South Sea in Korea, and investigated using a polyphasic taxonomic approach. Strain DPG-21(T) grew optimally at pH 7.0-8.0, at 30 °C and in the presence of 2% (w/v) NaCl. In a neighbour-joining phylogenetic tree based on 16S rRNA gene sequences, strain DPG-21(T) clustered with Tropicimonas isoalkanivorans B51(T) (with a sequence similarity of 97.1%); the novel strain showed lower 16S rRNA gene sequence similarities (<95.4%) with the other species included in the tree. The mean DNA-DNA relatedness value between strain DPG-21(T) and T. isoalkanivorans DSM 19548(T) was 12%. The predominant ubiquinones of strain DPG-21(T) were Q-10 and Q-9 while C(18:1)ω7c was the strain's major fatty acid. The polar lipid profile of strain DPG-21(T) was similar to that of T. isoalkanivorans DSM 19548(T). The genomic DNA G+C content of the novel strain was 69.6 mol%. Some phenotypic properties and the phylogenetic and genetic data indicated that strain DPG-21(T) was distinct from T. isoalkanivorans and represents a novel species of the genus Tropicimonas, for which the name Tropicimonas aquimaris sp. nov. is proposed. The type strain is DPG-21(T) (=KCTC 23424(T)=CCUG 60524(T)).

Pseudorhodobacter aquimaris sp. nov., isolated from seawater, and emended description of the genus Pseudorhodobacter Uchino et al. 2002.

A Gram-stain-negative, aerobic, motile, ovoid bacterial strain, designated HDW-19(T), was isolated from seawater of the west coast of Korea and subjected to a polyphasic taxonomic study. Strain HDW-19(T) grew optimally at pH 7.0-8.0, at 30 °C and in the presence of 2-3% (w/v) NaCl. Bacteriochlorophyll a was not produced by strain HDW-19(T). Neighbour-joining, maximum-likelihood and maximum-parsimony phylogenetic trees based on 16S rRNA gene sequences showed that strain HDW-19(T) clustered with Pseudorhodobacter ferrugineus IAM 12616(T), with which it shared 96.4% similarity. A neighbour-joining phylogenetic tree based on gyrB gene sequences showed that strain HDW-19(T) also clustered with the type strain of P. ferrugineus, sharing 83.0% similarity. Strain HDW-19(T) contained Q-10 as the predominant ubiquinone and C(18:1)ω7c as the major fatty acid. The major polar lipids were phosphatidylcholine, phosphatidylglycerol, three unidentified aminophospholipids and two unidentified aminolipids. The DNA G+C content of strain HDW-19(T) was 60.9 mol%. Differential phenotypic properties, together with phylogenetic distinctiveness, showed that strain HDW-19(T) can be differentiated from P. ferrugineus. On this basis, strain HDW-19(T) is considered to represent a novel species of the genus Pseudorhodobacter, for which the name Pseudorhodobacter aquimaris sp. nov. is proposed. The type strain is HDW-19(T) (=KCTC 23043(T) =CCUG 58879(T)).

Virgibacillus campisalis sp. nov., from a marine solar saltern.

A Gram-staining-variable, motile, endospore-forming and rod-shaped bacterial strain, IDS-20(T), was isolated from a marine solar saltern in Korea and subjected to a polyphasic taxonomic investigation. Strain IDS-20(T) grew optimally at 37 °C, at pH 7.5-8.0 and in the presence of 4-5 % (w/v) NaCl. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain IDS-20(T) belongs to the genus Virgibacillus. Strain IDS-20(T) exhibited 93.4-96.6 % 16S rRNA gene sequence similarity to the type strains of species of the genus Virgibacillus. Strain IDS-20(T) had MK-7 as the predominant menaquinone and a cell-wall peptidoglycan based on meso-diaminopimelic acid. The major fatty acids were anteiso-C(15 : 0) and anteiso-C(17 : 0) and major polar lipids were diphosphatidylglycerol, phosphatidylglycerol and two unidentified phospholipids. The DNA G+C content was 39.5 mol%. The phylogenetic distinctiveness and differential phenotypic characteristics of strain IDS-20(T) demonstrated that this strain can be distinguished from recognized species of the genus Virgibacillus. On the basis of the data presented, strain IDS-20(T) represents a novel species of the genus Virgibacillus, for which the name Virgibacillus campisalis sp. nov. is proposed. The type strain is IDS-20(T) ( = KCTC 13727(T)  = CCUG 59308(T)).

Reclassification of the three species of the genus Krokinobacter into the genus Dokdonia as Dokdonia genika comb. nov., Dokdonia diaphoros comb. nov. and Dokdonia eikasta comb. nov., and emended description of the genus Dokdonia Yoon et al. 2005.

The genera Dokdonia and Krokinobacter, members of the family Flavobacteriaceae in the phylum Bacteroidetes, were found to be phylogenetically closely related from the result of 16S rRNA gene sequence analysis. Dokdonia donghaensis DSW-1(T) exhibited 16S rRNA gene sequence similarity values of 99.3, 98.1 and 98.1% to Krokinobacter genikus Cos-13(T), Krokinobacter diaphorus MSKK-32(T) and Krokinobacter eikastus PMA-26(T), respectively. A taxonomic study of D. donghaensis DSW-1(T), K. genikus CIP 108744(T), K. diaphorus CIP 108745(T) and K. eikastus CIP 108743(T) was conducted using a polyphasic approach. The major fatty acids (>10% of the total fatty acids) in the four strains were iso-C(15:0), iso-C(15:1) G and iso-C(17:0) 3-OH, and their overall fatty acid profiles were essentially similar. The predominant menaquinone found in the type strains of the three species of the genus Krokinobacter was MK-6, in line with the genus Dokdonia. The polar lipid profiles of the type strains of the three species of the genus Krokinobacter were similar to that of D. donghaensis DSW-1(T) in that phosphatidylethanolamine, one unidentified aminolipid and one unidentified lipid were the major polar lipids. In addition, one unidentified aminophospholipid was also present as a major polar lipid in K. diaphorus CIP 108745(T) and K. eikastus CIP 108743(T). D. donghaensis DSW-1(T) was distinguishable from K. genikus CIP 108744(T), K. diaphorus CIP 108745(T) and K. eikastus CIP 108743(T) by genetic relatedness and differential phenotypic properties. On the basis of these data, it is proposed that K. genikus, K. diaphorus and K. eikastus be reclassified into the genus Dokdonia as Dokdonia genika comb. nov. (type strain is Cos-13(T) = NBRC 100811(T) = CIP 108744(T)), Dokdonia diaphoros comb. nov. (type strain is MSKK-32(T) = NBRC 100817(T) = CIP 108745(T)), and Dokdonia eikasta comb. nov. (type strain is PMA-26(T) = NBRC 100814(T) = CIP 108743(T)), respectively. An emended description of the genus Dokdonia is also presented.

Erythrobacter marinus sp. nov., isolated from seawater.

A Gram-negative, non-motile, ovoid to rod-shaped bacterium, designated strain HWDM-33(T), was isolated from seawater of the Yellow Sea, Korea, and was subjected to a polyphasic taxonomic study. Strain HWDM-33(T) grew optimally at pH 7-8, at 25 °C and in the presence of 2-3 % (w/v) NaCl. Neighbour-joining, maximum-likelihood and maximum-parsimony phylogenetic trees based on 16S rRNA gene sequences showed that strain HWDM-33(T) clustered with Erythrobacter gangjinensis K7-2(T), with which it shared 96.9 % sequence similarity. Strain HWDM-33(T) exhibited 94.2-95.8 % 16S rRNA gene sequence similarity to the type strains of other recognized species of the genus Erythrobacter. Strain HWDM-33(T) contained Q-10 as the predominant ubiquinone and C(18 : 1)ω7c, C(17:1)ω6c, and C(16:1)ω7c and/or iso-C(15 : 0) 2-OH as the major fatty acids. The major polar lipids were sphingoglycolipid, phosphatidylglycerol, phosphatidylcholine, phosphatidylethanolamine and an unidentified lipid. The DNA G+C content of strain HWDM-33(T) was 66.1 mol%. Differential phenotypic properties and phylogenetic distinctiveness demonstrated that strain HWDM-33(T) was separate from E. gangjinensis and other recognized species of the genus Erythrobacter. On the basis of the data presented here, strain HWDM-33(T) represents a novel species of the genus Erythrobacter, for which the name Erythrobacter marinus sp. nov. is proposed. The type strain is HWDM-33(T) (= KCTC 23554(T) = CCUG 60528(T)).

Marinomonas hwangdonensis sp. nov., isolated from seawater.

A Gram-negative, motile, rod-shaped bacterial strain, designated HDW-15(T), was isolated from seawater of the Yellow Sea, Korea, and subjected to a polyphasic taxonomic study. Strain HDW-15(T) grew optimally at pH 7.0-8.0, at 25 °C and in the presence of 2 % (w/v) NaCl. Phylogenetic analyses based on 16S rRNA gene sequences revealed that strain HDW-15(T) fell within the clade comprising Marinomonas species, joining the type strain of Marinomonas arctica, with which it exhibited highest 16S rRNA gene sequence similarity (97.7 %). The 16S rRNA gene sequence similarity values between strain HDW-15(T) and the type strains of other Marinomonas species were in the range 93.7-97.2 %. Mean DNA-DNA relatedness values between strain HDW-15(T) and the type strains of M. arctica, Marinomonas polaris and Marinomonas pontica were 5.0-9.9 %. The DNA G+C content of the isolate was 48.7 mol%. Strain HDW-15(T) contained Q-8 as the predominant ubiquinone and C(18 : 1)ω7c, summed feature 3 (C(16 : 1)ω7c and/or iso-C(15 : 0) 2-OH) and C(16 : 0) as the major fatty acids. The major polar lipids found in strain HDW-15(T) were phosphatidylglycerol and phosphatidylethanolamine. Differential phenotypic properties, together with phylogenetic and genetic distinctiveness, showed that strain HDW-15(T) can be differentiated from other Marinomonas species. On the basis of the data presented, strain HDW-15(T) is considered to represent a novel species of the genus Marinomonas, for which the name Marinomonas hwangdonensis sp. nov. is proposed. The type strain is HDW-15(T) (= KCTC 23661(T) = CCUG 61321(T)).

Celeribacter baekdonensis sp. nov., isolated from seawater, and emended description of the genus Celeribacter Ivanova et al. 2010.

A Gram-stain-negative, non-motile, ovoid or rod-shaped bacterial strain, designated L-6(T), was isolated from seawater of Baekdo harbour of the East Sea in Korea and its taxonomic position was investigated by using a polyphasic study. Strain L-6(T) grew optimally at 30 °C, at pH 7.5-8.0 and in the presence of 2 % (w/v) NaCl. In the neighbour-joining phylogenetic tree based on 16S rRNA gene sequences, strain L-6(T) formed a cluster with the type strain of Celeribacter neptunius at a bootstrap resampling value of 100 %. Strain L-6(T) exhibited 16S rRNA gene sequence similarity values of 97.7 % to C. neptunius H 14(T) and of less than 96.2 % to the type strains of other species used in the phylogenetic analysis. The G+C content of the chromosomal DNA of strain L-6(T) was 60.9 mol%. The predominant ubiquinone found in strain L-6(T) and C. neptunius CIP 109922(T) was ubiquinone-10 (Q-10). The predominant fatty acid of strain L-6(T) and C. neptunius CIP 109922(T) was C(18:1)ω7c. The major polar lipids of strain L-6(T) were phosphatidylglycerol, one unidentified aminolipid and one unidentified lipid. The mean level of DNA-DNA relatedness between strain L-6(T) and C. neptunius CIP 109922(T) was 17 %. Differential phenotypic properties, together with phylogenetic and genetic distinctiveness, demonstrated that strain L-6(T) is distinguishable from C. neptunius. On the basis of the data presented, strain L-6(T) is considered to represent a novel species of the genus Celeribacter, for which the name Celeribacter baekdonensis sp. nov. is proposed. The type strain is L-6(T) ( = KCTC 23497(T) = CCUG 60799(T)).

Namhaeicola litoreus gen. nov., sp. nov., a member of the family Flavobacteriaceae isolated from seawater.

A Gram-staining-negative, non-flagellated, non-gliding and pleomorphic bacterial strain, designated DPG-25(T), was isolated from seawater in a seaweed farm in the South Sea in Korea and its taxonomic position was investigated by using a polyphasic approach. Strain DPG-25(T) grew optimally at 25 °C, at pH 7.0-7.5 and in the presence of 2 % (w/v) NaCl. Flexirubin-type pigments were not produced. Phylogenetic analyses based on 16S rRNA gene sequences revealed that strain DPG-25(T) formed a cluster with the type strains of Actibacter sediminis, Aestuariicola saemankumensis and Lutimonas vermicola. Strain DPG-25(T) exhibited 16S rRNA gene sequence similarity values of 95.3, 93.1 and 93.6 % to the type strains of Actibacter sediminis, Aestuariicola saemankumensis and L. vermicola, respectively. Strain DPG-25(T) contained MK-6 as the predominant menaquinone and iso-C(15 : 0) and iso-C(17 : 0) 3-OH as the major fatty acids. The major polar lipids detected in strain DPG-25(T) were phosphatidylethanolamine and one unidentified lipid. The DNA G+C content was 39.9 mol%. Differential phenotypic properties and the phylogenetic distinctiveness of strain DPG-25(T) demonstrated that this strain is distinguishable from Actibacter sediminis, Aestuariicola saemankumensis and L. vermicola. On the basis of the data presented here, strain DPG-25(T) represents a novel species in a novel genus of the family Flavobacteriaceae, for which the name Namhaeicola litoreus gen. nov., sp. nov. is proposed. The type strain of Namhaeicola litoreus is DPG-25(T) (= KCTC 23702(T) = CCUG 61485(T)).