Solitalea lacus sp. nov., isolated from pond sediment.

A Gram-stain-negative, strictly aerobic, oxidase-positive, catalase-negative, motile by gliding, creamy white-pigmented bacterium, designated strain S2-8T, isolated from a sediment sample from a Wiyang pond in the Republic of Korea, was subjected to polyphasic taxonomic analysis. Growth was observed at 10-40 °C (optimum: 30 °C), pH 7-8 and 0-0.5% NaCl. Phylogenetic analyses based on 16S rRNA gene sequences revealed that strain S2-8T belonged to the family Sphingobacteriaceae in the phylum Bacteroidota and was closely related to Solitalea longa HR-AVT, Solitalea canadensis DSM 3403T and Solitalea koreensis R2A36-4T with 97.2, 96.7 and 93.7 % 16S rRNA gene sequence similarities, respectively. Average nucleotide identity and digital DNA-DNA hybridization values for these type strains were 72.0-75.2% and 21.2-21.9 %, respectively. The major respiratory quinone is menaquinone-7. The major fatty acids were iso-C15 : 0, iso-C17 : 0 3-OH and summed feature 3 (comprising C16 : 1 ω7c and/or C16 : 1 ω6c). The major polar lipids were phosphatidylethanolamine, two unidentified amino acids and four unidentified lipids. The G+C content of genomic DNA was 37.9 mol%. Based on polyphasic taxonomic analysis, it was observed that strain S2-8T is a novel species belonging to the genus Solitalea, for which the name Solitalea lacus sp. nov. is proposed. The type strain is S2-8T (= KACC 22266T= JCM 34533T).

Flavobacterium nackdongense sp. nov., a cellulose-degrading bacterium isolated from sediment.

A Gram-negative, non-motile, rod-shaped bacterial strain, designated GS13T, was isolated from sediments in a branch of the Nackdong River in Sangju, Korea. Optimal growth occurred at pH 7.0, 20 °C, and 0% NaCl. Phylogenetic analyses using 16S rRNA showed that strain GS13T is a member of the genus Flavobacterium, with highest similarity to Flavobacterium soyangense IMCC26223T (97.0%). The DNA G+C content of strain GS13T was 36.2 mol%. The dominant fatty acids were summed feature 3 (C16:1ω7c and/or C16:1ω6c) and iso-C15:0. The major polar lipids were phosphatidylethanolamine, three unidentified aminolipids, three unidentified lipids, and one unidentified aminophospholipid. The predominant respiratory quinone was MK-6. Our data demonstrate that strain GS13T can be distinguished from closely-related Flavobacterium species. Thus, strain GS13T is a novel Flavobacterium species, and we propose the name Flavobacterium nackdongense sp. nov. The type strain is GS13T (=KCTC 62569T = JCM 32765T).

High-level production of poly-γ-glutamic acid from untreated molasses by Bacillus siamensis IR10.

BACKGROUND: Poly-γ-glutamic acid (γ-PGA) is a promising biopolymer and has been applied in many fields. Bacillus siamensis SB1001 was a newly isolated poly-γ-glutamic acid producer with sucrose as its optimal carbon source. To improve the utilization of carbon source, and then molasses can be effectively used for γ-PGA production, 60cobalt gamma rays was used to mutate the genes of B. siamensis SB1001. RESULTS: Bacillus siamensis IR10 was screened for the production of γ-PGA from untreated molasses. In batch fermentation, 17.86 ± 0.97 g/L γ-PGA was obtained after 15 h, which is 52.51% higher than that of its parent strain. Fed-batch fermentation was performed to further improve the yield of γ-PGA with untreated molasses, yielding 41.40 ± 2.01 g/L of γ-PGA with a productivity of 1.73 ± 0.08 g/L/h. An average γ-PGA productivity of 1.85 g/L/h was achieved in the repeated fed-batch fermentation. This is the first report of such a high γ-PGA productivity. The analysis of the enzyme activities showed that they were affected by the carbon sources, enhanced ICDH and GDH, and decreased ODHC, which are important for γ-PGA production. CONCLUSION: These results suggest that untreated molasses can be used for economical and industrial-scale production of γ-PGA by B. siamensis IR10.

Simultaneous production of poly-γ-glutamic acid and 2,3-butanediol by a newly isolated Bacillus subtilis CS13.

Bacillus subtilis naturally produces large amounts of 2,3-butanediol (2,3-BD) as a main by-product during poly-γ-glutamic acid (γ-PGA) production. 2,3-BD is a promising platform chemical in various industries, and co-production of the two chemicals has great economic benefits. Co-production of γ-PGA and 2,3-BD by a newly isolated B. subtilis CS13 was investigated here. The fermentation medium and culture parameters of the process were optimized using statistical methods. It was observed that sucrose, L-glutamic acid, ammonium citrate, and MgSO4·7H2O were favorable for γ-PGA and 2,3-BD co-production at culture pH of 6.5 and 37 °C. An optimal medium composed of 119.8 g/L sucrose, 48.8 g/L L-glutamic acid, 21.1 g/L ammonium citrate, and 3.2 g/L MgSO4·7H2O was obtained by response surface methodology (RSM). The results show that the titers of γ-PGA and 2,3-BD reached 27.8 ± 0.9 g/L at 24 h and 57.1 ± 1.3 g/L at 84 h with the optimized medium, respectively. γ-PGA and 2,3-BD production by B. subtilis CS13 was significantly enhanced in fed-batch fermentations. γ-PGA (36.5 ± 1.1 g/L, productivity of 1.22 ± 0.04 g/L/h) and 2,3-BD concentrations (119.6 ± 2.8 g/L, productivity of 2.49 ± 0.66 g/L/h) were obtained in the optimized medium with feeding sucrose. The co-production of 2,3-BD and γ-PGA provides a new perspective for industrial production of γ-PGA and 2,3-BD. Key points • A strategy for co-production of γ-PGA and 2,3-BD was developed. • The culture parameters for the co-production of γ-PGA and 2,3-BD were studied. • RSM was used to optimize the medium for γ-PGA and 2,3-BD co-production. • 36.5 g/L γ-PGA and 119.6 g/L 2,3-BD were obtained from the optimum medium in fed-batch fermentation.

Chryseobacterium salivictor sp. nov., a plant-growth-promoting bacterium isolated from freshwater.

A Gram-stain-negative, non-motile, rod-shaped bacterial strain, designated NBC 122T, was isolated from freshwater of the Nakdong River Republic of Korea. Growth occurred at pH 5.0-8.0 (optimum, pH 7.0), at 4-37 °C (optimum, 25 °C), and with 0-3.5% (w/v) NaCl (optimum, 1%). Phylogenetic analyses based on 16S rRNA gene sequences showed that strain NBC 122T belongs to the genus Chryseobacterium and is most closely related to Chryseobacterium antarcticum AT1013T (97.85%). The average nucleotide identity and in silico DNA-DNA hybridization (DDH) values between strain NBC 122T and related Chryseobacterium species were 77.77-80.28 and 20.9-23.2%, respectively. The strain NBC 122T contained MK-6 as the major respiratory quinone. The major fatty acids included anteiso C15:0, iso C15:0, summed feature 9 (C17:1 iso ω9c, C16:0 10-methyl) and iso C17:0 3-OH, and the polar lipids were phosphatidylethanolamine, five unidentified aminolipids and six unidentified lipids. The DNA G + C content was 37.5 mol%. On the basis of a 16S rRNA gene phylogeny and comparative phenotypic analyses, strain NBC 122T represents a novel species in the genus Chryseobacterium, for which the name Chryseobacterium salivictor sp. nov. is proposed. The type strain is NBC122T (= KCTC 72248T = JCM 33980T).

Ephemeroptericola cinctiostellae gen. nov., sp. nov., isolated from gut of an aquatic insect.

A Gram-stain-negative, catalase- and oxidase-positive, non-motile bacterium, designated F02T, was isolated from of gut of Cincticostellalevanidovae (Tshernova). Growth occurred at a temperature range of 4-30 °C, at pH 6-9 and in the presence of 0-0.5 % (w/v) NaCl. Phylogenetic analysis demonstrated that the 16S rRNA gene sequence of strain F02T shared the highest similarity to that of the type strain of Hydromonas duriensis A2P5T (96.82 %). The major isoprenoid quinone was Q-8. The polar lipids were diphosphatidylglycerol, phosphatidylglycerol and phosphatidylethanolamine. The major cellular fatty acids were summed feature 3 (C16 : 1ω7c/C16 : 1ω6c) and iso-C13 : 0 3-OH. The polyamines were cadaverine and putrescine. Combined data from phylogenetic, phenotypic and chemotaxonomic analyses demonstrated that strain F02T represents a novel genus and species, for which the name Ephemeroptericolacinctiostellae gen. nov., sp. nov. is proposed. The type strain of Ephemeroptericola cinctiostellae gen. nov., sp. nov. is F02T (=FBCC 500047T=KCTC 62567T=JCM 32722T).

Flavobacterium sangjuense sp. nov. isolated from sediment.

A yellow-pigmented bacterial strain, GS03T, was isolated from sediment in a branch of the Nackdong River in Sangju, Korea. Cells were observed to be Gram-negative, aerobic and rod-shaped with gliding motility, and to be positive for catalase and oxidase. Growth was found to occur at 4-30 °C (optimum 25 °C), at pH 7.0-8.5 (optimum pH 7.5) and at NaCl 0% (optimum NaCl 0%, w/v). The major cellular fatty acids (> 10% of the total) were identified as iso C15:0, iso C15:1 G, C15:1ω6c, iso C15: 0 3-OH and iso C17: 0 3-OH. The major respiratory quinone was found to be menaquinone MK-6. The genome sequence of GS03T is 3.1 Mb with G+C content of 36.1 mol%. The major polar lipids of the isolate were identified as phosphatidylethanolamine, three unidentified aminolipids, two unidentified phospholipids, an unidentified lipid and an unidentified aminophospholipid. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain GS03T clusters with Flavobacterium paronense KNUS1TT, with similarity of 96.8%. The phenotypic, phylogenetic, and chemotaxonomic characteristics indicate that strain GS03T represents a novel species of the genus Flavobacterium, for which the name Flavobacterium sangjuense sp. nov. is proposed. The type strain is GS03T (= FBCC 502459T = KCTC 62568T = JCM 32764T).

Sphingobacterium praediipecoris sp. nov. isolated from effluent of a dairy manure treatment plant.

A novel Gram-reaction-negative, rod-shaped, non-motile bacterium, designated as strain G2-10T was isolated from effluent of a dairy manure treatment plant. Growth occurred at 20-40 °C (optimum at 25-30 °C), pH 7.0-8.0 (optimum at pH 7.0). The range of NaCl concentration for growth was between 0% and 3% (w/v) (optimum 0-1%, w/v). Comparison of 16S rRNA gene sequence indicated that strain G2-10T was moderately related to the type strains of Sphingobacterium nematocida M-SX103T and Sphingobacterium suaedae T47T with a pair-wise sequence similarity of 94.3% and 94.0%, respectively. The major fatty acid constituents of strain G2-10T were identified as iso-C15:0 (37.6%), summed feature 3 (consisting of C16:1ω7c and/or C16:1ω6c, 29.6%) and iso-C17:0 3-OH (15.2%). Phosphatidylethanolamine was the major polar lipids of strain G2-10T. Sphingophospholipids were present. The isoprenoid quinone was composed of only MK-7. The DNA G + C content of strain G2-10T was found to be 42.5 mol%. The phenotypic, chemotaxonomic and phylogenetic properties suggest that strain G2-10T represents a novel species within the genus Sphingobacterium, for which the name Sphingobacterium praediipecoris is proposed. The type strain is G2-10T (= KCTC 52880T = NBRC 112848T).

Lacinutrix chionocetis sp. nov., isolated from gut of a red snow crab.

A Gram-negative, aerobic, non-motile, rod-shaped bacterial strain, designated MAB-07T, was isolated from the gut of a red snow crab. The novel strain grew optimally at 20 °C, pH 7.0-8.0, and in the presence of 3% (w/v) NaCl. A phylogenetic analysis based on the 16S rRNA gene sequence indicated that the strain MAB-07T belongs to the type strains of species of the genus Lacinutrix. Strain MAB-07T exhibited 16S rRNA gene sequence similarity values of 95.5-97.8% with the type strains of species of the genus Lacinutrix. The predominant cellular fatty acids of strain MAB-07T were iso-C15:1 G (27.5%) and iso-C15:0 (21.7%). The major respiratory quinine was identified as MK-6. The polar lipids consisted of phosphatidylethanolamine, four unidentified aminolipids, and two unidentified lipids. The genomic DNA G + C content was determined to be 33.3%, and its DNA-DNA relatedness values with the type strains of L. venerupis, L. mariniflava, L. jangbogonensis, L. algicola, and Olleya aquimaris were 28-32%. Based on the data from this polyphasic taxonomic study, strain MAB-07T is considered to represent a novel species of the genus Lacinutrix, for which the name L. chionocetis sp. nov. is proposed. The type strain is MAB-07T (=KCTC 42767T = JCM 30988T).

Pre-elafin is Involved in Ultraviolet-induced Keratinocyte Apoptosis via Pro-caspase-3 Activation Associated with Cystatin-A Down-regulation.

Pre-elafin controls keratinocyte integrity via cornified envelope formation and inhibition of desquamation, but its role in ultraviolet (UV)-induced keratinocyte apoptosis is unknown. This study examined the role of pre-elafin in volunteer skin samples and primary cultured normal human keratinocytes irradiated with phototoxic doses of UVA/narrow-band UVB, and in keratinocytes with pre-elafin overexpression/knockdown, under conditions of low and high calcium. Phototoxic doses of UV increased pre-elafin mRNA and protein expression in inverse proportion to keratinocyte survival. Pre-elafin overexpression under conditions of low calcium, which, in contrast to conditions of high calcium, was localized to the cytoplasm, increased keratinocyte apoptosis, whereas knockdown inhibited UV-induced apoptosis. Pre-elafin was co-localized with, but not bound to, cleaved caspase-3. Pre-elafin reduced cystatin-A expression, which was bound to pro-caspase-3. In conclusion, UV phototoxicity-induced pre-elafin inside keratinocytes prior to cornified envelope formation could be involved in UV-induced keratinocyte apoptosis via cystatin-A downregulation resulting in pro-caspase-3 activation.

Reduced Nrf2 activation in PI3K phosphorylation-impaired vitiliginous keratinocytes increases susceptibility to ROS-generating chemical-induced apoptosis.

Keratinocytes in affected epidermis of vitiligo patients are known to have impaired activation of the PI3K/AKT pathway. Based on critical roles of keratinocytes and oxidative stress in vitiligo development, this study examined whether keratinocytes with impaired PI3K activation were more vulnerable to apoptosis caused by oxidative stress from phenolic compounds, p-tert-butylphenol (4-TBP) and hydroquinone (HQ). Cell viability assay, FACS analysis, ELISA for TNF-α or IL-1a, ROS assay, Western blot analysis for Nrf2 expression, and confocal microscopy with anti-Nrf2 and phospho-PI3K antibodies were done on primary cultured normal human keratinocytes with or without PI3K knockdown in the presence or absence of chemical treatment or antioxidant. Immunofluorescence staining using anti-Nrf2, phospho-PI3K, TNF-ɑ, and IL-1ɑ antibodies, ROS assay using dihydroethidium, and TUNEL assay were performed on sets of depigmented and normally pigmented skin from vitiligo patients. Results showed that 4-TBP or HQ treatment increased apoptosis and the expression levels of TNF-ɑ, IL-1ɑ, and ROS in PI3K-knockdown keratinocytes which reduced Nrf2 nuclear translocation compared to control keratinocytes. These changes were significantly recovered by an antioxidant treatment. Depigmented epidermis of vitiligo patients also showed lower levels of Nrf2 and phospho-PI3K but higher levels of ROS, TNF-ɑ, IL-1ɑ, and ROS with more TUNEL-positive cells. Therefore, impaired PI3K activation in keratinocytes in depigmented epidermis of vitiligo patients are vulnerable to apoptosis caused by ROS-generating chemicals due to reduced Nrf2 activation.

Jejuia marina nov., isolated from gravel adjacent to Geommeolle beach on Udo Island, South Korea.

A bacterial strain, JH03(T), was isolated from gravel adjacent to Geommeolle beach on Udo Island, South Korea. The cells were Gram-stain-negative, aerobic, non-motile and rod shaped. The ranges of temperature, pH and NaCl concentration for growth of the bacterium were 10-45 °C, pH 6.0-9.5 and 0.5-5.0 % (w/v), respectively. The major fatty acids of the bacterium were iso-C(15:0) (15.4 %), iso-C(15:1) G (14.1 %), iso-C(16:0) 3-OH (14.1 %), iso-C(17:0) 3-OH (11.5 %) and anteiso-C(15:0) (11.3 %). The major isoprenoid quinone was MK-6. The polar lipids included phosphatidylethanolamine, two unidentified amino lipids and three unidentified lipids. The DNA G+C content was 34.2 mol%. The phylogenetic analysis of the 16S rRNA gene sequences showed that strain JH03(T) was most closely related to Jejuia pallidilutea EM39(T) (96.5 % sequence similarity). Based on the polyphasic analysis, strain JH03(T) is a novel species of the genus Jejuia, for which the name Jejuia marina sp. nov. is proposed. The type strain is JH03(T) (= KCTC 42342(T) = JCM 30601(T)).

Hyunsoonleella udoensis sp. nov., isolated from a gravel sample from a beach of Udo island, Korea.

A Gram-stain negative, non-motile, rod-shaped and aerobic bacterial strain, designated JG48(T), was isolated from a gravel sample taken from a beach adjacent to Udo island, South Korea. Strain JG48(T) was found to grow optimally at 25 °C, at pH 7.0-8.0 and in the presence of 2.0 % (w/v) NaCl. The 16S rRNA gene sequence of strain JG48(T) exhibited sequence similarities of 96.67 % to Hyunsoonleella jejuensis CNU004(T). The major fatty acids present in the strain JG48(T) were identified as iso-C15:0, iso-C15:1 G, iso-C17:0 3-OH and iso-C15:0 3-OH. The predominant isoprenoid quinone was identified as MK-6. The polar lipids profile of strain JG48(T) was found to consist of phosphatidylethanolamine, three unidentified amino lipids and four unidentified lipids. The DNA G+C content of strain JG48(T) was determined to be 34 mol%. Based on the morphological and physiological properties, and the results of phylogenetic analyses, the strain is considered to represent a novel species of the genus Hyunsoonleella, for which the name Hyunsoonleella udoensis sp. nov. is proposed. The type strain is JG48(T) (=KCTC 42341(T)=JCM 30600(T)).

Aestuariivita boseongensis gen. nov., sp. nov., isolated from a tidal flat sediment.

A Gram-stain-negative, aerobic, non-motile and coccoid, ovoid or rod-shaped bacterial strain, BS-B2(T), which was isolated from a tidal flat sediment at Boseong in South Korea, was characterized taxonomically. Strain BS-B2(T) grew optimally at 30 °C, at pH 7.0-8.0 and in the presence of 2.0 % (w/v) NaCl. The novel strain exhibited highest 16S rRNA gene sequence similarity (97.4 %) to Marivita geojedonensis DPG-138(T). Neighbour-joining, maximum-likelihood and maximum-parsimony phylogenetic trees based on 16S rRNA gene sequences revealed that strain BS-B2(T) is closely related to Primorskyibacter sedentarius KMM 9018(T), showing 96.5 % sequence similarity. Strain BS-B2(T) contained Q-10 as the predominant ubiquinone and C18 : 1ω7c as the predominant fatty acid. The polar lipid profile of strain BS-B2(T) comprised phosphatidylcholine, phosphatidylglycerol, one unidentified aminolipid and one unidentified lipid as major components, and differentiated it from the type strains of P. sedentarius and M. geojedonensis. The DNA G+C content of strain BS-B2(T) was 62.2 mol%. Differential phenotypic properties, together with the phylogenetic and chemotaxonomic data, demonstrated that strain BS-B2(T) can be distinguished from phylogenetically related genera as well as P. sedentarius and M. geojedonensis. On the basis of the data presented, strain BS-B2(T) is considered to represent a novel species of a new genus, for which the name Aestuariivita boseongensis gen. nov., sp. nov. is proposed. The type strain of Aestuariivita boseongensis is BS-B2(T) ( = KCTC 42052(T) = CECT 8532(T)).

Luteimicrobium xylanilyticum sp. nov., isolated from the gut of a long-horned beetle, Massicus raddei.

A novel strain, designated W-15(T), was isolated from the gut of a long-horned beetle, Massicus raddei, collected in South Korea. Phylogenetic analysis based on 16S rRNA gene sequences revealed that the strains belonged to the suborder Micrococcineae. Strain W-15(T) was most closely related to Luteimicrobium album RI148-Li105(T) (97.9 % similarity). Strain W-15(T) was Gram-stain-positive, rod- and coccus-shaped and non-motile. Growth was observed at 15-37 °C, at pH 4.5-8.5 and in the presence of 0-5.0 % NaCl. The cell-wall peptidoglycan of the strain was A4α (l-Lys-d-Ser-d-Asp). The major menaquinone present in this strain was MK-8 (H2) and the major cellular fatty acids were anteiso-C15 : 0, iso-C16 : 0, iso-C15 : 0 and anteiso-C17 : 0. The major polar lipids were diphosphatidylglycerol, phosphatidylinositol, an unknown lipid, an unknown phospholipid and an unknown phosphoglycolipid. The G+C content of genomic DNA of the strain was 73.8 mol%. On the basis of evidence from our polyphasic taxonomic study, strain W-15(T) is classified as representing a novel species in the suborder Micrococcineae, for which the name Luteimicrobium xylanilyticum sp. nov. is proposed. The type strain of this species is strain W-15(T) ( = KCTC 19882(T) = JCM 18090(T)).

Sphingorhabdus arenilitoris sp. nov., isolated from a coastal sand, and reclassification of Sphingopyxis rigui as Sphingorhabdus rigui comb. nov. and Sphingopyxis wooponensis as Sphingorhabdus wooponensis comb. nov.

A Gram-stain-negative, strictly aerobic, non-flagellated and rod-shaped bacterial strain, designated GJR-7(T), was isolated from coastal sand of the South Sea of South Korea. Strain GJR-7(T) grew optimally at 30 °C, at pH 7.0-7.5 and without NaCl. Phylogenetic trees based on 16S rRNA gene sequences revealed that strain GJR-7(T) clustered with the type strains of Sphingopyxis wooponensis, Sphingopyxis rigui and Sphingorhabdus planktonica, with which it exhibited 16S rRNA gene sequence similarity values of 96.0-96.3%. Sequence similarities to the type strains of other recognized species were less than 95.5%. Strain GJR-7(T) contained Q-10 as the predominant ubiquinone and C(18 : 1)ω7c, 11-methyl C(18 : 1)ω7c and summed feature 3 (C(16 : 1)ω7c and/or C(16 : 1)ω6c) or C(14 : 0) 2-OH. The major polar lipids were sphingoglycolipid, phosphatidylcholine, phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol and one unidentified glycolipid. The DNA G+C content of strain GJR-7(T) was 55.5 mol%. Differential phenotypic properties, together with phylogenetic distinctiveness, revealed that strain GJR-7(T) is separated from the type strains of Sphingopyxis wooponensis, Sphingopyxis rigui and Sphingorhabdus planktonica. On the basis of the data presented, strain GJR-7(T) is considered to represent a novel species of the genus Sphingorhabdus, for which the name Sphingorhabdus arenilitoris sp. nov. is proposed. The type strain is GJR-7(T) ( = KCTC 42051(T) = CECT 8531(T)). It is also proposed that Sphingopyxis wooponensis and Sphingopyxis rigui should be reclassified as members of the genus Sphingorhabdus.

Design, synthesis and biological evaluation of benzyl 2-(1H-imidazole-1-yl) pyrimidine analogues as selective and potent Raf inhibitors.

The synthesis of a novel series of (4-aminobenzyl/benzoyl)-1H-imidazol-1-yl pyrimidin-2-yl derivatives 9, 10, 18, 19 and their in vitro antiproliferative activities against the A375P human melanoma cell line and the U937 human leukemic monocyte lymphoma cell line are described. Potent antiproliferative effects were found from 9l, 9s and 10c; 10c was found to be a highly potent and selective BRAF V600E and CRAF inhibitor (IC50=38.3 nM and 8.79 nM).

Halocynthiibacter namhaensis gen. nov., sp. nov., a novel alphaproteobacterium isolated from sea squirt Halocynthia roretzi.

A Gram-negative, non-motile and rod-shaped bacterial strain, designated RA2-3(T), was isolated from a sea squirt (Halocynthia roretzi) collected from the South Sea, Korea, and its taxonomic position was investigated by using a polyphasic approach. Strain RA2-3(T) was observed to grow optimally at 25 °C, at pH 7.0-7.5 and in the presence of 2 % (w/v) NaCl. Strain RA2-3(T) exhibited the highest 16S rRNA gene sequence similarity values to the type strains of Litoreibacter meonggei (95.7 %), Planktotalea frisia (95.6 %), Thalassobius gelatinovorus (95.5 %) and Pelagicola litoralis (95.4 %). A neighbour-joining phylogenetic tree based on 16S rRNA gene sequences revealed that strain RA2-3(T) clustered with the type strains of Planktotalea frisia, Pelagicola litoralis, Pacificibacter maritimus and Roseovarius marinus. Strain RA2-3(T) was found to contain Q-10 as the predominant ubiquinone and C18:1 ω7c as the major fatty acid. The major polar lipids detected in strain RA2-3(T) were phosphatidylcholine, phosphatidylglycerol, one unidentified aminolipid and one unidentified lipid. The DNA G+C content of strain RA2-3(T) was 52.9 mol%. On the basis of the phylogenetic, chemotaxonomic and phenotypic properties, strain RA2-3(T) is considered to represent a new genus and species within the family Rhodobacteraceae, for which the name Halocynthiibacter namhaensis gen. nov., sp. nov. is proposed. The type strain of H. namhaensis is RA2-3(T) (=KCTC 32362(T)=NBRC 109999(T)).

Antarctobacter jejuensis sp. nov., isolated from seawater in Jeju, Korea.

A novel bacterium, designated strain 13-2-B6(T), was isolated from seawater adjacent to Songak Mountain on Jeju Island, South Korea. The novel strain was observed to be Gram-negative, aerobic, rod-shaped and motile with a single polar flagellum. On the basis of 16S rRNA gene sequence similarity, strain 13-2-B6(T) was determined to be phylogenetically closely related to the type strain of Antarctobacter heliothermus, currently the sole species of the genus Antarctobacter (family Rhodobacteraceae). Sequence similarity between the 16S rRNA genes of strain 13-2-B6(T) and A. heliothermus EL-219(T) is 96.9 %. Strain 13-2-B6(T) was found to grow optimally at 25-30 °C, pH 7.0-8.0 and 3 % (w/v) NaCl. The predominant isoprenoid quinone in strain 13-2-B6(T) was identified as ubiquinone Q-10 and the major fatty acids were identified as C18:1 ω7c and/or C18:1 ω6c. Phosphatidylglycerol, diphosphatidylglycerol, phosphatidylethanolamine, two unknown aminolipids, two unknown phospholipids, an unknown glycolipid and an unknown lipid were found to be components of the polar lipid profile. The G + C content of strain 13-2-B6(T) was determined to be 62 mol %. On the basis of its phenotypic, chemotaxonomic and phylogenetic distinctiveness, strain 13-2-B6(T) is considered to represent a novel species of the genus Antarctobacter, for which the name Antarctobacter jejuensis sp. nov. is proposed. The type strain is 13-2-B6(T) (=KCTC 42009(T) =JCM 19898(T)).

Pseudoruegeria limi sp. nov. isolated from mud flats in the Yellow Sea in Korea.

A Gram-negative, aerobic, non-motile and rod-shaped bacterial strain, D-17(T), was isolated from mud flats in the Yellow Sea in Korea. Phylogenetic trees based on the 16S rRNA gene sequence showed that strain D-17(T) belongs to the genus Pseudoruegeria and it shared 97.5 % similarity with the type strain of Pseudoruegeria haliotis WM67(T). The sequence similarities with Pseudoruegeria litimaris HD-43(T) and Pseudoruegeria aquimaris SW-255(T) were 96.9 and 96.1 %, respectively. Strain D-17(T) was found to grow with 0.5-6 % (w/v) NaCl, at 20-30 °C, and at pH 6.5-8.0. Strain D-17(T) was determined to contain Q-10 as the predominant ubiquinone and summed feature 8 (C18:1 ω7c and/or C18:1 ω6c, as defined by the MIDI system) as the major fatty acids. The major polar lipids were identified as phosphatidylglycerol, diphosphatidylglycerol, an unidentified aminolipid, an unidentified glycolipid, an unidentified lipid and four unidentified phospholipids. The DNA G+C content was determined to be 63.6 mol%. The DNA-DNA relatedness with P. haliotis WM67(T) was 32.5 %. The differential phenotypic properties revealed that strain D-17(T) can be separated from other Pseudoruegeria species. Based on the data presented in this study, strain D-17(T) represents a novel species, for which the name Pseudoruegeria limi sp. nov. is proposed. The type strain is D-17(T) (=KCTC 32460(T) =JCM 19487(T)).