Mesoflavibacter zeaxanthinifaciens gen. nov., sp. nov., a novel zeaxanthin-producing marine bacterium of the family Flavobacteriaceae

A novel strictly aerobic, gliding, Gram-negative, rod-shaped, halo- and mesophilic bacterium (TD-ZX30(T)) was isolated from a seawater sample collected on the Pacific coastline of Japan near Kamakura City (Fujisawa, Kanagawa). The temperature range for growth of TD-ZX30(T) was between 16 and 44 degrees C. The DNA G+C content was 32.0mol%. The predominant fatty acids were iso-C(15:1) G, iso-C(15:0), iso-C(16:0) 3-OH, iso-C(15:0) 3-OH, Summed feature (iso-C(15:0) 2-OH and/or C(16:1)omega7c), iso-C(17:0) 3-OH, and C(15:0). MK-6 was the only respiratory quinone. Zeaxanthin was the major carotenoid pigment produced but flexirubin-type pigments were not produced. Phylogenetic analysis based on the 16S rRNA gene sequence revealed that TD-ZX30(T) belonged to a distinct lineage in the family Flavobacteriaceae, sharing 93.9% sequence similarity with the nearest species Olleya marilimosa. TD-ZX30(T) could be distinguished from the other members of the family Flavobacteriaceae by a number of chemotaxonomic and phenotypic characteristics. The results of polyphasic taxonomic analyses suggested that TD-ZX30(T) represents a novel genus and a novel species, for which the name Mesoflavibacter zeaxanthinifaciens gen. nov., sp. nov. is proposed. The type strain is TD-ZX30(T) (=NBRC 102119=CCUG 53614=DSM 18436).     

Siansivirga zeaxanthinifaciens gen. nov., sp. nov., a novel zeaxanthin-producing member of the family Flavobacteriaceae isolated from coastal seawater of Taiwan

A strictly aerobic, Gram-negative, rod-shaped bacterium (strain CC-SAMT-1(T)) showing gliding motility was isolated from coastal seawater of China Sea, Taiwan. Strain CC-SAMT-1(T) synthesizes all-trans-zeaxanthin (6.5 ± 0.5 mg g(-1) dry biomass) as a predominant xanthophyll carotenoid. As determined by 16S rRNA gene analysis, strain CC-SAMT-1(T) shared very high sequence similarity to the members of the genera Mariniflexile (96.1-95.3%) and Gaetbulibacter (96.0-95.9%); however, it formed a distinct phyletic lineage distantly associated with Mariniflexile species. Polar lipid profile constitutes phosphatidylethanolamine, four unidentified aminolipids, four unidentified lipids, and an unidentified glycolipid. Strain CC-SAMT-1(T) contains excessive unidentified aminolipid lipid (AL2-4) and glycolipid contents, and therefore clearly distinct from Mariniflexile species. Major fatty acids (> 5% of total fatty acids) were iso-C(15:0) (14.8%), iso-C(17:0) 3-OH (11.8%), iso-C(15:1) G (10.6%), anteiso-C(15:0) (9.7%), C(16:0) (8.1%), iso-C(16:0) 3-OH (7.9%), iso-C(15:0) 3-OH (7.5%), and summed feature 3 (containing C(16:1) ω6c and/or C(16:1) ω7c) (7.5%). Menaquinone-6 (MK-6) was major respiratory quinone. DNA G+C content was 33.7 mol%. Based on polyphasic taxonomy, strain CC-SAMT-1(T) represents a novel genus and species in the family Flavobacteriaceae for which the name Siansivirga zeaxanthinifaciens gen. nov., sp. nov. is proposed. The type strain is CC-SAMT-1(T) (= BCRC 80315(T) = JCM 17682(T)).     

Wangia profunda gen. nov., sp. nov., a novel marine bacterium of the family Flavobacteriaceae isolated from southern Okinawa Trough deep-sea sediment

An orange-pigmented, Gram-negative, nonmotile, strictly aerobic and oxidase- and catalase-positive bacterium (SM-A87(T)) was isolated from the deep-sea sediment of the southern Okinawa Trough area. The main fatty acids were i15 : 0, i17 : 0 3OH, i15 : 1 G, i17 : 1 omega 9c, 15 : 0, i15 : 0 3OH and summed feature 3 (comprising i-15 : 0 2OH and/or 16 : 1 omega 7c). MK-6 was the predominant respiratory quinone. DNA G+C content was 35.8 mol%. Flexirubin-type pigments were absent. Phylogenetic analyses based on 16S rRNA gene sequences revealed that strain SM-A87(T) formed a distinct lineage within the family Flavobacteriaceae, with <93% sequence similarity to the nearest strain of genus Salegentibacter. Moreover, strain SM-A87(T) could be distinguished from the nearest phylogenetic neighbors by a number of chemotaxonomic and phenotypic properties. On the basis of polyphasic analyses, it is proposed that strain SM-A87(T) be classified in a novel genus and a new species in the family Flavobacteriaceae, designated Wangia profunda gen. nov., sp. nov. The type strain is SM-A87(T) (CCTCC AB 206139(T)=DSM 18752).     

Myroides profundi sp. nov., isolated from deep-sea sediment of the southern Okinawa Trough

A Gram-negative, nonmotile, aerobic and oxidase- and catalase-positive bacterium, designated D25(T), was isolated from the deep-sea sediments of the southern Okinawa Trough area. Phylogenetic analyses of 16S rRNA gene sequences showed that strain D25(T) fell within the genus Myroides, with 99.2%, 96.0% and 93.4% sequence similarities to the only three recognized species of Myroides. However, the DNA-DNA similarity value between strain D25(T) and its nearest neighbour Myroides odoratimimus JCM 7460(T) was only 49.9% (<70%). Several phenotypic properties could be used to distinguish strain D25(T) from other Myroides species. The main cellular fatty acids of strain D25(T) were iso-C(15:0), iso-C(17:1)omega9c, iso-C(17:0)3-OH and Summed Feature 3 (comprising C(16:1)omega7c and/or iso-C(15:0)2-OH). The major respiratory quinone was MK-6. The DNA G+C content was 33.0 mol%. The results of the polyphasic taxonomy analysis suggested that strain D25(T) represents a novel species of the genus Myroides, for which the name Myroides profundi sp. nov. is proposed. The type strain is D25(T) (=CCTCC M 208030(T)=DSM 19823(T)).     

Croceibacter atlanticus gen. nov., sp. nov., a novel marine bacterium in the family Flavobacteriaceae

A bright, saffron-colored marine bacterium HTCC2559T was isolated from the Bermuda Atlantic Time Series station in the western Sargasso Sea, Atlantic Ocean by high throughput culturing methods and characterized by polyphasic approaches. Phenotypic data and phylogenetic analyses showed that the strain is a member of the family Flavobacteriaceae. The strain was gram-negative, non-motile, chemoheterotrophic, strictly aerobic, NaCl-requiring, rod-shaped cells that contain carotenoid pigments but not flexirubin. Several kinds of macromolecules (gelatin, DNA, starch, casein, and elastin) were degraded and carbohydrates, sugar alcohols, organic acids, and amino acids were utilized as sole carbon sources. The dominant fatty acids were branched or hydroxy acids, and 3-OH i17:0, i15:0, i15:1, and i17:1 omega9c were abundant. The DNA G+C content of the strain is 34.8 mol%. Phylogenetic analyses using three treeing algorithms based on 16S rRNA gene sequences revealed that the strain formed a very distinct lineage that is allied closely with several seawater environmental clones in the family Flavobacteriaceae. Therefore, it is proposed from the polyphasic studies that strain HTCC2559T (=ATCC BAA-628T = KCTC 12090T) belongs to a new genus and species named Croceibacter atlanticus gen. nov., sp. nov.     

Pukyongia salina gen. nov., sp. nov., a novel genus in the family Flavobacteriaceae

A Gram-negative aerobic bacterium, designated RR4-38T, was isolated from a biofilter in a seawater recirculating aqua-culture system (RAS) in Busan, South Korea. The bacteria were irregular, short, rod-shaped, non-motile, oxidase-positive, and catalase-negative. Growth of the strain RR4-38T was observed at 15–35·C (optimum, 25–30·C), pH 5.5–9.5 (optimum, pH 8.0), and in the presence of 0–5% (w/v) NaCl (optimum, 3%). Phylogenetic analysis based on the 16S rRNA gene sequences showed that the strain RR4-38T formed a distinct lineage with close genera Ulvibacter (≤ 95.01% 16S rRNA gene sequence similarity), Aureitalea (94.74%), Aureisphaera (≤ 93.27%), and Jejudonia (93.07%) that all belong to the family Flavobacteriaceae. Whole-genome sequence comparison revealed that the ANI (average nucleotide identity) and digital DDH (DNA-DNA hybridization) values between strain RR4-38T and the two closest strains, Ulvibacter antarcticus DSM 23424T and Aureitalea marina S1-66T, were 68.96–69.88% and 17.4–19%, respectively. The genome analysis revealed that the strain might be involved in biodegradation of organic debris produced by farmed fish in aquaculture systems. The predominant respiratory quinone was menaquinone MK-6 and the major cellular fatty acids were iso-C15:0 (26.5%), iso-C17:0 3-OH (16.4%), iso-C15:1 G (15%), and iso-C16:0 3-OH (9.6%). The major cellular polar lipids were diphosphatidylglycerol, phosphatidylethanolamine, unidentified aminolipids, and glycolipids. Based on phenotypic, chemotaxonomic, and phylogenetic features, strain RR4-38t represents a novel genus and species in the family Flavobacteriaceae, for which the name Pukyongia salina gen. nov., sp. nov. is proposed. The type strain is RR4-38T (= KCTC 52651T = DSM 108068T).     

Sufflavibacter maritimus gen. nov., sp. nov., novel Flavobacteriaceae bacteria isolated from marine environments

Four Gram-negative, chemoheterotrophic, nonmotile, yellow-colored strains were isolated from the East Sea or from deep-sea sediments of Nankai Trough by standard dilution plating. Characterization by polyphasic approaches indicated that the four strains are members of the same species. Phylogenetic analyses based on 16S rRNA gene sequences revealed that the strains formed a coherent and novel genus-level lineage within the family Flavobacteriaceae. The dominant cellular fatty acids were i-C15:0, 3-OH i-C17:0, and 2-OH i-C15:0 and/or C16:1 omega7c. Predominance of 2-OH i-C 15:0 and/or C16:1omega7c clearly differentiated the strains from closely related members. The DNA G+C contents ranged 35.1-36.2 mol%. It is proposed, from the polyphasic evidence, that the strains should be placed into a novel genus and species named Sufflavibacter maritimus gen. nov., sp. nov., with strain IMCC 1001T (=KCCM 42359T=NBRC 102039T) as the type strain.     

Leucobacter exalbidus sp. nov., an actinobacterium isolated from a mixed culture from compost

A gram-positive bacterium, strain K-540B(T), which was separated from a mixed culture isolated from compost, was subjected to a polyphasic taxonomic study. Strain K-540B(T) was found to have 95.5%-98.7% sequence similarity with the genus Leucobacter based on 16S rRNA gene sequence analyis. Phenotypic and chemical properties of strain K-540B(T) were consistent with its classification in the genus Leucobacter. The major quinone system compound was MK-11 and major fatty acids were anteiso-C(15:0) and iso-C(16:0). Polar lipids included phosphatidylglycerol and diphosphatidylglycerol. The G+C content of the genomic DNA was 64.9 mol%. The cell wall peptidoglycan contained diaminobutyric acid and γ-aminobutyric acid. DNA-DNA hybridization results and physiological tests genotypically and phenotypically differentiated strain K-540B(T) from other Leucobacter species. Based on these results, strain K-540B(T) (=NBRC 106062(T)=DSM 22850(T)), for which the name Leucobacter exalbidus sp. nov. is proposed, represents a novel species of the genus Leucobacter.     

Cohnella panacarvi sp. nov., a xylanolytic bacterium isolated from ginseng cultivating soil

A Gram-positive, aerobic, rod-shaped, nonmotile, endospore-forming bacterium, designated Gsoil 349T, was isolated from soil of a ginseng field and characterized using a polyphasic approach. Comparative analysis of 16S rRNA gene sequences revealed that the strain Gsoil 349T belongs to the family Paenibacillaceae, and the sequence showed closest similarity with Cohnella thermotolerans DSM 17683T (94.1%) and Cohnella hongkongensis DSM 17642T (93.6%). The strain showed less than 91.3% 16S rRNA gene sequence similarity with Paenibacillus species. In addition, the presence of MK-7 as the major menaquinone and anteiso-C(15:0), iso-C(16:0), and C(16:0) as major fatty acids suggested its affiliation to the genus Cohnella. The G+C content of the genomic DNA was 53.4 mol%. On the basis of its phenotypic characteristics and phylogenetic distinctiveness, strain Gsoil 349T should be treated as a novel species within the genus Cohnella for which the name Cohnella panacarvi sp. nov. is proposed. The type strain is Gsoil 349T (=KCTC 13060T = DSM 18696T).     

Flavobacterium ginsengiterrae sp. nov., isolated from a ginseng field

A novel strain of Flavobacterium, DCY55(T), a Gram-negative, yellow-pigmented, rod-shaped, non-spore-forming and gliding-motile bacterium, was isolated from the soil of a ginseng field in South Korea. Phylogenetic analysis, based on the 16S rRNA sequence, demonstrated that strain DCY55(T) belongs to the genus Flavobacterium within the family Flavobacteriaceae. Strain DCY55(T) showed the highest similarity with F. johnsoniae UW101(T) (97.1%), F. ginsenosidimutans THG 01(T) (96.8%), F. defluvii EMB 117(T) (96.6%), F. banpakuense 15F3(T) (96.3%) and F. anhuiense D3(T) (95.8%). Chemotaxonomic results showed that strain DCY55(T) predominantly contains menaquinone MK-6, that its DNA G+C content is 36.1mol%, and that its major cellular fatty acids are iso-C(15:0), summed feature 3 (comprising iso-C(15:0) 2-OH and/or C(16:1) ω 7c) and C(16:0). The chemotaxonomic and genotypic characteristics support the taxonomic classification of strain DCY55(T) to the genus Flavobacterium. The results of physiological and biochemical tests confirmed that strain DCY55(T) is distinct from previously validated species. We conclude that strain DCY55(T) should be classified as a novel species of the genus Flavobacterium, for which the name Flavobacterium ginsengiterrae sp. nov. is proposed, with the type strain DCY55(T) (=KCTC 23319(T) = JCM 17337(T)).     

Flavobacterium cheonhonense sp. nov., isolated from a freshwater reservoir

A novel bacterium, designated strain ARSA-15(T), was isolated from a freshwater sample collected from the Cheonho reservoir, Cheonan, Republic of Korea. The isolate was deep-yellow pigment, Gram-negative, rod-shaped, non-motile, and catalase- and oxidase-positive. Phylogenetic analysis based on 16S rRNA gene sequences showed that the isolate belongs to the genus Flavobacterium, and shared less than 97% sequence similarity with recognized Flavobacterium species. The novel species was able to grow at 10-37°C, pH 6.5-10.0, and in 0-0.5% (w/v) NaCl concentrations. Chemotaxonomically, iso-C(15:1), iso-C(15:0), and iso-C(16:0) were observed to be the predominant cellular fatty acid, and menaquinone-6 (MK-6) was the predominant respiratory quinone. The major polar lipid patterns of strain ARSA-19(T) was phosphatidylethanolamine, unknown aminolipid (AL1 and AL2), and unidentified polar lipids (L1, L2, and L3). The genomic DNA G+C content of the isolate was 39.2 mol%. On the basis of polyphasic approach, strain ARSA-15(T) represents a novel species of the genus Flavobacterium, for which the name Flavobacterium cheonhonense sp. nov. is proposed. The type strain is ARSA-15(T) (=KACC 14967(T) =KCTC 23180(T) =JCM 17064(T)).     

Psychrosphaera saromensis gen. nov., sp. nov., within the family Pseudoalteromonadaceae, isolated from Lake Saroma, Japan

Three Gram-negative, motile, coccoid- and ellipsoidal-shaped, non-pigmented, chemoheterotrophic bacteria, designated strains SA4-31, SA4-46 and SA4-48(T), were isolated from Lake Saroma in Japan and subjected to a polyphasic taxonomical study. 16S rRNA gene sequence analysis revealed that the novel isolates could be affiliated to the family Pseudoalteromonadaceae of the order Alteromonadales. The strains shared approximately 99.7-100% sequence similarity with each other and showed 89.5-93.2% similarity with members of the family Pseudoalteromonadaceae with validly published names. The DNA-DNA relatedness among the strains SA 4-31, SA 4-46 and SA 4-48(T) was higher than 80%, a value that is accepted as a phylogenetic definition of one species. The DNA G+C contents of the three strains were 38.7-39.6 mol%. The major isoprenoid quinone was Q-8 and C16:0, C16:1 ω7c, C18:1 ω7c and C12:1 3OH were the major fatty acids. Based on the evidence from the polyphasic taxonomical study, it was concluded that the three strains should be classified as representing a new genus and species of the family Pseudoalteromonadaceae, for which the name Psychrosphaera saromensis gen. nov., sp. nov. (type strain SA4-48(T) =NBRC 107123(T)= KCTC 23240(T)) is proposed.     

Saccharopolyspora endophytica sp. nov., an endophytic actinomycete isolated from the root of Maytenus austroyunnanensis

A Gram-positive, aerobic, non-motile, non-acid-alcohol-fast strain, designated YIM 61095(T), was isolated from the root of Maytenus austroyunnanensis collected from a tropical rainforest of Xishuangbanna in Yunnan Province, south-west China. Strain YIM 61095(T) exhibited chemotaxonomic and morphological characteristics that were consistent with members of the genus Saccharopolyspora. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain YIM 61095(T) was a member of the genus Saccharopolyspora and was most closely related to Saccharopolyspora flava AS 4.1520(T) (97.7% sequence similarity). The major fatty acids were iso-C(15:0), iso-C(16:0), iso-C(17:0) and anteiso-C(17:0). The predominant quinone detected was MK-9(H(4)). The DNA G+C content was 66.2 mol%. The phenotypic characteristics and DNA-DNA hybridization relatedness data indicated that strain YIM 61095(T) should be distinguished from Saccharopolyspora flava AS 4.1520(T). On the basis of the evidence presented in this study, strain YIM 61095(T) represents a novel species of the genus Saccharopolyspora, for which the name Saccharopolyspora endophytica sp. nov. is proposed. The type strain is YIM 61095(T) (=KCTC 19397(T)=CCTCC AA 208003(T)).     

Shivajiella indica gen. nov., sp. nov., a marine bacterium of the family "Cyclobacteriaceae" with nitrate reducing activity

Novel orange pigmented, Gram-negative-staining, rod-shaped, non-motile, strictly aerobic strains designated NIO-S1(T) and NIO-S2 were isolated from the water sample of a pond adjacent to the coast and an algal mat from a fish pond, respectively, at Kakinada, India. Both strains were positive for oxidase, catalase and β-galactosidase activities. The predominant fatty acids in NIO-S1(T) were iso-C(15:0) (39.6%), anteiso-C(15:0) (9.9%), iso-C(17:0) 3OH (10.9%) and C(16:1)ω7c/C(16:1)ω6c (summed feature 3) (5.7%). The strains contained MK-7 as the major respiratory quinine, and diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine and three unidentified lipids as the polar lipids. Phylogenetic analysis indicated that strain NIO-S1(T) was a member of the family "Cyclobacteriaceae" of the class "Sphingobacteriia" and it clustered with the genera Fontibacter, Cecembia and Aquiflexum with phylogenetic distances of 6.8, 9.0 and 12.2% (93.2, 91.0 and 87.8% similarity), respectively. DNA-DNA hybridization between strains NIO-S1(T) and NIO-S2 showed a relatedness of 93% and rep-PCR banding patterns were similar. Based on data from the current polyphasic study, it is proposed that the new isolates be placed in a new genus and species with the name Shivajiella indica gen. nov., sp. nov. The type strain of Shivajiella indica is NIO-S1(T) (= KCTC 19812(T)=MTCC 11065(T)).     

<i>Portibacter lacus</i> gen. nov., sp.nov., a new member of the family <i>Saprospiraceae</i> isolated from a saline lake

A strictly aerobic, Gram-negative, orange-pigmented, rod-shaped, non-motile and chemoheterotrophic bacteria representing a new genus and species, designated YM8-076^T, was isolated from lake water collected at a harbor on Lake Notoro, Hokkaido, Japan. Preliminary analysis based on the 16S rRNA gene sequence revealed that the novel isolate could be affiliated with the family Saprospiraceae of the phylum Bacteroidetes and that it showed highest sequence similarity (88.5%) to Haliscomenobacter hydrossis ATCC 27775^T. The strain could be differentiated phenotypically from recognized members of the family Saprospiraceae. The G+C content of DNA was 53.7 mol%, MK-7 was the major menaquinone and iso-C15：0, iso-C15：1 and iso-C17：0 3-OH were the major cellular fatty acids. On the basis of polyphasic taxonomic studies, it was concluded that strain YM8-076^T represents a new genus and species of the family Saprospiraceae. We propose the name Portibacter lacus gen. nov., sp. nov. for this strain; its type strain is YM8-076^T (=KCTC 23747^T=NBRC 108769^T).     

Luedemannella gen. nov., a new member of the family Micromonosporaceae and description of Luedemannella helvata sp. nov. and Luedemannella flava sp. nov

Three actinomycete strains were isolated from soil samples collected in Bangladesh. The cultures formed spherical sporangia on short sporangiophores directly above the surface of the substrate mycelium. The sporangia developed singly or in clusters and each sporangium contained several nonmotile spherical to oval spores with a smooth surface. The strains 3-9(24)(T), 3-21(27) and 7-40(26)(T) contained meso-diaminopimelic acid in the cell walls, predominant menaquinone MK-9(H(6)) and MK-9(H(4)) and glucose, xylose, galactose, mannose, rhamnose, ribose and arabinose in the whole-cell hydrolysates. Diagnostic phospholipid is phosphatidylethanolamine and branched anteiso-C(17 : 0) (30.0-38.0%), anteiso-C(15 : 0) (12.5-14.0%), iso-C(16 : 0) (10.0-15.0%) and iso-C(15 : 0) (10.0-12.0%) were detected as the major cellular fatty acids. The acyl type of the peptidoglycan was glycolyl and mycolic acids were not detected. The G+C content of the DNA was 71 mol%. The chemotaxonomic data indicate that these strains belong to the family Micromonosporaceae. Phylogenetic analysis based on 16S rRNA gene sequence data suggested that the strains 3-9(24)(T), 3-21(27) and 7-40(26)(T) fall within the family Micromonosporaceae. On the basis of phylogenetic analysis and characteristic patterns of signature nucleotides as well as morphological and chemotaxonomic data, Luedemannella gen. nov. is proposed for our 3 isolates. DNA-DNA hybridization experiment and phenotypic characterization indicated that the new genus was constituted of 2 species, as Luedemannella helvata sp. nov. for the strain 3-9(24)(T) (=JCM 13249(T)=MTCC 8091(T)) and Luedemannella flava for the strain 7-40(26)(T) (=JCM 13250(T)=MTCC 8095(T)) in the family Micromonosporaceae.     

Nocardioides tritolerans sp. nov., Isolated from soil in Bigeum Island, Korea

A Gram-positive strain designated as MSL-14T isolated from a soil sample collected from Bigeum Island, Korea, was subjected to polyphasic taxonomy. The isolate was strictly aerobic. Cells were short rods and motile. Optimum growth temperature and pH was 28 degrees and 7.0, respectively. It was characterized chemotaxonomically as having a cell-wall peptidoglycan type based on LL-2,6-diaminopimelic acid and MK-8(H4) as the predominant menaquinone. The major fatty acids were iso-C16:0, C17:1 omega8c, and C18:1 omega9c. The G+C content was 67.6 mol%. Phylogenetic analysis based on the 16S rRNA gene sequence revealed that strain MSL-14T is affiliated to the genus Nocardioides and formed a distinct lineage within the genus. MSL-14T showed highest sequence similarity to Nocardioides aestuarii JCM 12125T, having a similarity of 96.5%. Based on the 16S rRNA gene sequence divergence and phenotypic characteristics, it is proposed that strain MSL-14T should be classified as representing a novel member of the genus Nocardioides, for which we propose the name Nocardioides tritolerans sp. nov. The type strain is strain MSL-14T (=KCTC 19289T= DSM 19320T).     

Chryseobacterium oncorhynchi sp. nov., isolated from rainbow trout (Oncorhynchus mykiss)

Genotypic and phenotypic analyses were performed on five Gram-negative, catalase and oxidase-positive, rod-shaped bacteria isolated from the gill and liver of four rainbow trout. Studies based on comparative 16S rRNA gene sequence analysis showed that the five new isolates shared 99.8-100% sequence similarity and that they belong to the genus Chryseobacterium. The nearest phylogenetic neighbours of the strain 701B-08(T) were Chryseobacterium ureilyticum F-Fue-04IIIaaaa(T) (99.1% 16S rRNA gene sequence similarity) and Chryseobacterium joosteii LMG 18212(T) (98.6%). DNA-DNA hybridization values between the five isolates were 91-99% and ranged from 2 to 53% between strain 701B-08(T) and the type strains of phylogenetically closely related species of Chryseobacterium. Strain 701B-08(T) had a DNA G+C content of 36.3 mol%, the major fatty acids were iso-C(15:0), iso-C(17:1)ω9c, C(16:1)ω6c and iso-C(17:0) 3-OH and the predominant respiratory quinone was MK-6. The novel isolates were distinguished from related Chryseobacterium species by physiological and biochemical tests. The genotypic and phenotypic properties of the isolates from rainbow trout suggest their classification as representatives of a novel species of the genus Chryseobacterium, for which the name Chryseobacterium oncorhynchi sp. nov. is proposed. The type strain is 701B-08(T) (=CECT 7794(T)=CCUG 60105(T)).     

Thalassobius aestuarii sp. nov., isolated from tidal flat sediment

A strictly aerobic, non-motile, ovoid-shaped Alphaproteobacteria, designated strain JC2049(T), was isolated from a tidal flat sediment sample. The results of 16S rRNA gene sequence analysis indicated that this isolate belonged to the genus Thalassobius, with a sequence similarity of 96.9-97.3% to other valid Thalassobius spp. The cells required 1-7% NaCl for growth (optimum 2%) and accumulated poly-beta-hydroxybutyrate. Nitrite was reduced to nitrogen, but nitrate was not reduced to nitrite. No genetic potential for aerobic anoxygenic photosynthesis was detected. The primary isoprenoid quinone (Ubiquinone-10), predominant cellular fatty acids (C(18:1)omega7c, 11 methyl C(18:1)omega7c and C(16:0)) and DNA G+C content (61 mol%) were all consistent with the assignment of this isolate to the genus Thalassobius. Several phenotypic characteristics clearly distinguished our isolate from other Thalassobius species. The degree of genomic relatedness between strain JC2049(T) and other Thalassobius species was in a range of 20-43%. The polyphasic data presented in this study indicates that our isolate should be classified as a novel species within the genus Thalassobius. The name Thalassobius aestuarii sp. nov. is therefore proposed for this isolate; the type strain is JC2049(T) (= IMSNU 14011(T) = KCTC 12049(T) = DSM 15283(T)).     

Paradesulfovibrio onnuriensis gen. nov., sp. nov., a chemolithoautotrophic sulfate-reducing bacterium isolated from the Onnuri vent field of the Indian Ocean and reclassification of Desulfovibrio senegalensis as Paradesulfovibrio senegalensis comb. nov.

An anaerobic, rod-shaped, mesophilic, chemolithoautotrophic, sulfate-reducing bacterial strain IOR2T was isolated from a newly found deep-sea hydrothermal vent (OVF, Onnuri Vent Field) area in the central Indian Ocean ridge (11°24′88″ S 66°25′42″ E, 2021 m water depth). The 16S rRNA gene sequence analysis revealed that the strain IOR2T was most closely related to Desulfovibrio senegalensis BLaC1T (96.7%). However, it showed low similarity with the members of the family Desulfovibrionaceae, such as Desulfovibrio tunisiensis RB22T (94.0%), D. brasiliensis LVform1T (93.9%), D. halophilus DSM 5663T (93.7%), and Pseudodesulfovibrio aespoeensis Aspo-2T (93.2%). The strain IOR2T could grow at 23–42°C (optimum 37°C), pH 5.0–8.0 (optimum pH 7.0) and with 0.5–6.5% (optimum 3.0%) NaCl. The strain could use lactate, pyruvate, H2, and glycerol as electron donors and sulfate, thiosulfate, and sulfite as electron acceptors. The major fatty acids of the strain IOR2T were iso-C15:0, iso-C17:0, ante-iso-C15:0, and summed feature 9 (C16:0 methyl/iso-C17:1ω9c). Both the strains IOR2T and BLaC1T could grow with CO2 and H2 as the sole sources of carbon and energy, respectively. Genomic evidence for the Wood-Ljungdahl pathway in both the strains reflects chemolithoautotrophic growth. The DNA G + C content of the strain IOR2T and BLaC1T was 58.1–60.5 mol%. Based on the results of the phylogenetic and physiologic studies, Paradesulfovibrio onnuriensis gen. nov., sp. nov. with the type strain IOR2T (= KCTC 15845T = MCCC 1K04559T) was proposed to be a member of the family Desulfovibrionaceae. We have also proposed the reclassification of D. senegalensis as Paradesulfovibrio senegalensis comb. nov.