Burkholderia diazotrophica sp. nov., isolated from root nodules of Mimosa spp.

Five strains, JPY461(T), JPY359, JPY389, DPU-3 and STM4206 were isolated from nitrogen-fixing nodules on the roots of Mimosa spp. and their taxonomic positions were investigated using a polyphasic approach. All five strains grew at 15-40 °C (optimum, 30-37 °C), at pH 4.0-8.0 (optimum, pH 6.0-7.0) and with 0-1 % (w/v) NaCl [optimum, 0 % (w/v)]. On the basis of 16S rRNA gene sequence analysis, a representative strain (JPY461(T)) showed 97.2 % sequence similarity to the closest related species Burkholderia acidipaludis SA33(T), a similarity of 97.2 % to Burkholderia terrae KMY02(T), 97.1 % to Burkholderia phymatum STM815(T) and 97.1 % to Burkholderia hospita LMG 20598(T). The predominant fatty acids of the five novel strains were summed feature 2 (comprising C(16 : 1) iso I and/or C(14 : 0) 3-OH), summed feature 3 (comprising C(16 : 1)ω7c and/or C(16 : 1)ω6c), C(16 : 0) , C(16 : 0) 3-OH, C(17 : 0) cyclo, C(18 : 1)ω7c and C(19 : 0) cyclo ω8c. The major isoprenoid quinone was Q-8 and the DNA G+C content of the strains was 63.0-65.0 mol%. The polar lipid profile consisted of a mixture of phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol, an unidentified aminophospholipid, an unidentified aminolipid and several unidentified phospholipids. The DNA-DNA relatedness of the novel strain with respect to recognized species of the genus Burkholderia was less than 54 %. On the basis of 16S rRNA and recA gene sequence similarities, chemotaxonomic and phenotypic data, the five strains represent a novel species in the genus Burkholderia, for which the name Burkholderia diazotrophica sp. nov. is proposed with the type strain, JPY461(T) ( = LMG 26031(T) = BCRC 80259(T) = KCTC 23308(T)).

Burkholderia symbiotica sp. nov., isolated from root nodules of Mimosa spp. native to north-east Brazil.

Four strains, designated JPY-345(T), JPY-347, JPY-366 and JPY-581, were isolated from nitrogen-fixing nodules on the roots of two species of Mimosa, Mimosa cordistipula and Mimosa misera, that are native to North East Brazil, and their taxonomic positions were investigated by using a polyphasic approach. All four strains grew at 15-43 °C (optimum 35 °C), at pH 4-7 (optimum pH 5) and with 0-2 % (w/v) NaCl (optimum 0 % NaCl). On the basis of 16S rRNA gene sequence analysis, strain JPY-345(T) showed 97.3 % sequence similarity to the closest related species Burkholderia soli GP25-8(T), 97.3 % sequence similarity to Burkholderia caryophylli ATCC25418(T) and 97.1 % sequence similarity to Burkholderia kururiensis KP23(T). The predominant fatty acids of the strains were C(18 : 1)ω7c (36.1 %), C(16 : 0) (19.8 %) and summed feature 3, comprising C(16 : 1)ω7c and/or C(16 : 1)ω6c (11.5 %). The major isoprenoid quinone was Q-8 and the DNA G+C content of the strains was 64.2-65.7 mol%. The polar lipid profile consisted of a mixture of phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol and several uncharacterized aminophospholipids and phospholipids. DNA-DNA hybridizations between the novel strain and recognized species of the genus Burkholderia yielded relatedness values of <51.8 %. On the basis of 16S rRNA and recA gene sequence similarities and chemotaxonomic and phenotypic data, the four strains represent a novel species in the genus Burkholderia, for which the name Burkholderia symbiotica sp. nov. is proposed. The type strain is JPY-345(T) (= LMG 26032(T) = BCRC 80258(T) = KCTC 23309(T)).

Sphingomonas formosensis sp. nov., a polycyclic aromatic hydrocarbon-degrading bacterium isolated from agricultural soil.

In the present study, a yellow-pigmented, Gram-negative, short rod-shaped novel bacterium that was capable of degrading a wide range of polycyclic aromatic hydrocarbons (naphthalene, phenanthrene and pyrene) was isolated from agricultural soil located in Yunlin County, Taiwan. Comparative 16S rRNA gene sequence analysis positioned the novel strain in the genus Sphingomonas as an independent lineage adjacent to a subclade containing Sphingomonas fennica K101(T), Sphingomonas histidinilytica UM2(T), Sphingomonas wittichii RW1(T) and Sphingomonas haloaromaticamans A175(T). 16S rRNA gene sequence analysis of strain CC-Nfb-2(T) showed highest sequence similarity to S. fennica K101(T) (96.2%), S. histidinilytica UM2(T) (96.1%), S. wittichii RW1(T) (95.9%), S. haloaromaticamans A175(T) (95.7%), and Sphingobium ummariense RL-3(T) (94.7%); lower sequence similarities were observed with strains of all other Sphingomonas species. The strain contained phosphatidylcholine, phosphatidylethanolamine, phosphatidylglycerol, sphingoglycolipid and diphosphatidylglycerol. The predominant fatty acids were summed feature 8 (C(18:1)ω7c and/or C(18:1)ω6c) C(16:0) and 11-methyl C(18:1)ω7c; C(14:0) 2-OH was the major 2-hydroxy fatty acid. Previously, these lipids have been found to be characteristic of members of the genus Sphingomonas. The serine palmitoyl transferase gene (spt) was also detected and sphingolipid synthesis was confirmed. The predominant isoprenoid quinone system was ubiquinone (Q-10) and the isolate contained sym-homospermidine as the major polyamine. The DNA G+C content of the isolate was 62.8±0.8 mol%. On the basis of chemotaxonomic, phenotypic and phylogenetic data, strain CC-Nfb-2(T) represents a novel species within the genus Sphingomonas, for which the name Sphingomonas formosensis sp. nov. is proposed; the type strain is CC-Nfb-2(T) (=BCRC 80272(T)=DSM 24164(T)).

Burkholderia spp. are the most competitive symbionts of Mimosa, particularly under N-limited conditions.

Bacteria isolated from Mimosa nodules in Taiwan, Papua New Guinea, Mexico and Puerto Rico were identified as belonging to either the alpha- or beta-proteobacteria. The beta-proteobacterial Burkholderia and Cupriavidus strains formed effective symbioses with the common invasive species Mimosa diplotricha, M. pigra and M. pudica, but the alpha-proteobacterial Rhizobium etli and R. tropici strains produced a range of symbiotic phenotypes from no nodulation through ineffective to effective nodulation, depending on Mimosa species. Competition studies were performed between three of the alpha-proteobacteria (R. etli TJ167, R. tropici NGR181 and UPRM8021) and two of the beta-rhizobial symbionts (Burkholderia mimosarum PAS44 and Cupriavidus taiwanensis LMG19424) for nodulation of these invasive Mimosa species. Under flooded conditions, B. mimosarum PAS44 out-competed LMG19424 and all three alpha-proteobacteria to the point of exclusion. This advantage was not explained by initial inoculum levels, rates of bacterial growth, rhizobia-rhizobia growth inhibition or individual nodulation rate. However, the competitive domination of PAS44 over LMG19424 was reduced in the presence of nitrate for all three plant hosts. The largest significant effect was for M. pudica, in which LMG19424 formed 57% of the nodules in the presence of 0.5 mM potassium nitrate. In this host, ammonium also had a similar, but lesser, effect. Comparable results were also found using an N-containing soil mixture, and environmental N levels are therefore suggested as a factor in the competitive success of the bacterial symbiont in vivo.

Nodulation of Cyclopia spp. (Leguminosae, Papilionoideae) by Burkholderia tuberum.

BACKGROUND AND AIMS: Species of the genus Burkholderia, from the Betaproteobacteria, have been isolated from legume nodules, but so far they have only been shown to form symbioses with species of Mimosa, sub-family Mimosoideae. This work investigates whether Burkholderia tuberum strains STM678 (isolated from Aspalathus carnosa) and DUS833 (from Aspalathus callosa) can nodulate species of the South African endemic papilionoid genera Cyclopia (tribe Podalyrieae) and Aspalathus (Crotalarieae) as well as the promiscuous legume Macroptilium atropurpureum (Phaseoleae). METHODS: Bacterial strains and the phylogeny of their symbiosis-related (nod) genes were examined via 16S rRNA gene sequencing. Seedlings were grown in liquid culture and inoculated with one of the two strains of B. tuberum or with Sinorhizobium strain NGR 234 (from Lablab purpureus), Mesorhizobium strain DUS835 (from Aspalathus linearis) or Methylobacterium nodulans (from Crotalaria podocarpa). Some nodules, inoculated with green fluorescence protein (GFP)-tagged strains, were examined by light and electron microscopy coupled with immunogold labelling with a Burkholderia-specific antibody. The presence of active nitrogenase was checked by immunolabelling of nitrogenase and by the acetylene reduction assay. B. tuberum STM678 was also tested on a wide range of legumes from all three sub-families. KEY RESULTS: Nodules were not formed on any of the Aspalathus spp. Only B. tuberum nodulated Cyclopia falcata, C. galioides, C. genistoides, C. intermedia and C. pubescens. It also effectively nodulated M. atropurpureum but no other species tested. GFP-expressing inoculant strains were located inside infected cells of C. genistoides, and bacteroids in both Cyclopia spp. and M. atropurpureum were immunogold-labelled with antibodies against Burkholderia and nitrogenase. Nitrogenase activity was also shown using the acetylene reduction assay. This is the first demonstration that a beta-rhizobial strain can effectively nodulate papilioinoid legumes. CONCLUSIONS: Papilionoid legumes from widely different tribes can be nodulated by beta-rhizobia, forming both indeterminate (Cyclopia) and determinate (Macroptilium) nodules.

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)).

Fontibacter flavus gen. nov., sp. nov., a member of the family 'Cyclobacteriaceae', isolated from a hot spring.

The taxonomic position of a bright orange-pigmented bacterial strain, designated CC-GZM-130(T), isolated from a water sample of the Guan-zing-ling hot spring, southern Taiwan, was studied. The strain was able to grow on nutrient agar at 25-40 degrees C and in the presence of 1-3 % (w/v) NaCl. Comparative analyses of the 16S rRNA gene sequence showed that the isolate was grouped in the vicinity of the genus Aquiflexum with the highest sequence similarity of 92.1 % to the type strain of Aquiflexum balticum, followed by sequence similarities of 92.0, 91.6 and 91.5 % to the type strains of Algoriphagus ornithinivorans, Algoriphagus hitonicola and Belliella baltica, respectively. The polyamine pattern showed that the major compound was sym-homospermidine. The quinone system was menaquinone MK-7. The polar lipid profile was composed predominantly of phosphatidylethanolamine, three polar lipids and one aminolipid. Minor amounts of other lipids were also detectable. The main characteristics of the fatty acid profiles of strain CC-GZM-130(T), B. baltica and Aquiflexum balticum were similar, with iso-C(15 : 0), iso-C(17 : 1)ω 9c and iso-C(17 : 0) 3-OH as the major fatty acids, but some qualitative and quantitative differences were observed. The DNA G+C content of the novel strain was 53.2 mol%. The isolate clearly differed genotypically and phenotypically from representatives of the most closely related genera. On the basis of these differences, a novel species in a new genus, Fontibacter flavus gen. nov., sp. nov., is proposed with CC-GZM-130(T) (=CCUG 57694(T)=CCM 7650(T)) as the type strain of the type species.

Agaricicola taiwanensis gen. nov., sp. nov., an alphaproteobacterium isolated from the edible mushroom Agaricus blazei.

A Gram-negative, beige-pigmented, aerobic, motile, club-shaped bacterium, designated strain CC-SBABM117(T), was isolated from the stipe of the edible mushroom Agaricus blazei Murrill. 16S rRNA gene sequence analysis demonstrated that the strain shared <93 % similarity with the type strains of species in the genera Pannonibacter, Methylopila, Nesiotobacter and Stappia. The organism was unable to produce acid from carbohydrates, but utilized a number of organic acids and amino acids. Ubiquinone 10 (Q-10) was the major respiratory quinone and C(18 : 1) ω 7c, C(19 : 0) cyclo ω 8c, C(16 : 0) and C(18 : 0) were the predominant fatty acids. The predominant polar lipids were diphosphatidylglycerol, phosphatidylcholine, phosphatidylglycerol and phosphatidylethanolamine. The DNA G+C content of strain CC-SBABM117(T) was 62.7 mol%. On the basis of 16S rRNA gene sequence analysis and chemotaxonomic and physiological data, strain CC-SBABM117(T) is considered to represent a novel species of a new genus, for which the name Agaricicola taiwanensis gen. nov., sp. nov. is proposed. The type strain of Agaricicola taiwanensis is CC-SBABM117(T) (=BCRC 17964(T) =CCM 7684(T)).

Aquabacterium fontiphilum sp. nov., isolated from spring water.

A short-rod-shaped, Gram-negative, motile bacterial strain, designated CS-6(T), was isolated from a water sample collected from a spring located inside Nature Valley, Hsinchu County, Taiwan, and was characterized using a polyphasic approach. Phylogenetic analyses based on 16S rRNA gene sequences showed that the strain formed a monophyletic branch at the periphery of the evolutionary radiation occupied by the genus Aquabacterium in the class Betaproteobacteria. The closest neighbours were Aquabacterium parvum B6(T) (96.7 % sequence similarity), Aquabacterium commune B8(T) (96.6 %) and Aquabacterium citratiphilum B4(T) (95.9 %). The predominant fatty acids were 18 : 1omega7c (30.5 %), 16 : 0 (27.9 %) and summed feature 3 (16 : 1omega7c and/or iso-15 : 0 2-OH) (22.7 %). The DNA-DNA relatedness of the strain with respect to recognized species of the genus Aquabacterium was less than 70 %. The isolate was also distinguishable from members of the genus Aquabacterium on the basis of phenotypic and biochemical characteristics. It is evident from the genotypic, chemotaxonomic and phenotypic data, therefore, that strain CS-6(T) represents a novel species of the genus Aquabacterium, for which the name Aquabacterium fontiphilum sp. nov. is proposed. The type strain is CS-6(T) (=LMG 24215(T)=BCRC 17729(T)).

Paenibacillus contaminans sp. nov., isolated from a contaminated laboratory plate.

A bacterial strain, designated CKOBP-6T, isolated from a contaminated laboratory plate, was characterized by using a polyphasic taxonomic approach. Chemotaxonomic and morphological properties of the strain were consistent with its classification in the genus Paenibacillus. Cells were Gram-variable, aerobic, sporulating, motile rods. 16S rRNA gene sequence analysis demonstrated that this novel isolate was unique, showing 94.6 % sequence similarity to Paenibacillus chitinolyticus NBRC 15660T and lower levels of similarity to Paenibacillus gansuensis KCTC 3950T (93.8 %) and Paenibacillus terrigena A35T (93.8 %). The novel isolate could be distinguished from the type strains of all of these species based on a range of phenotypic data. The major cellular phospholipids were phosphatidylglycerol, diphosphatidylglycerol, phosphatidylethanolamine and one unknown phosphoglycolipid. The predominant isoprenologue was an unsaturated menaquinone with seven isoprene units (MK-7). The major fatty acids of strain CKOBP-6T were C(16 : 0) (12.0 %), anteiso-C(15 : 0) (52.0 %) and iso-C(16 : 0) (16.4 %). The G+C content of the genomic DNA was 51.2 mol%. It is evident from the genotypic and phenotypic data that strain CKOBP-6T should be classified as a representative of a novel species of the genus Paenibacillus, for which the name Paenibacillus contaminans sp. nov. is proposed. The type strain is CKOBP-6T (=BCRC 17728T=LMG 24216T).

Lutaonella thermophila gen. nov., sp. nov., a moderately thermophilic member of the family Flavobacteriaceae isolated from a coastal hot spring.

A yellow-pigmented, Gram-staining-negative, aerobic, non-motile, moderately thermophilic, rod-shaped bacterium, CC-MHSW-2T, was isolated from a coastal hot spring of Green Island (Lutao), located off Taituang, Taiwan. The 16S rRNA gene sequence analysis demonstrated that it shared <93.2% sequence similarity with Aquimarina species. The organism was unable to produce acid from carbohydrates, but it could utilize a number of organic acids and amino acids. Menaquinone 6 (MK-6) was the major respiratory quinone and iso-C15:0, iso-C17:0 3-OH and summed feature 3 (comprising C16:1omega7c and/or C16:1omega6c) were the predominant fatty acids. This fatty acid profile distinguished the isolate from members of the genera Aquimarina, Tamlana, Zhouia, Leeuwenhoekiella and Cellulophaga. The DNA G+C content of strain CC-MHSW-2T was 39.7+/-1 mol%. On the basis of the 16S rRNA gene sequence analysis and the chemotaxonomic and physiological data, strain CC-MHSW-2T represents a novel genus and species in the family Flavobacteriaceae, for which the name Lutaonella thermophila gen. nov., sp. nov. is proposed. The type strain is CC-MHSW-2T (=KCTC 22538T=JCM 15069T).

Vogesella lacus sp. nov., isolated from a soft-shell turtle culture pond.

A non-pigmented, Gram-negative, aerobic, rod-shaped bacterium, strain GR13(T), was isolated using nutrient agar from a water sample from a pond used for the culture of soft-shell turtles (Trionyx sinensis), Pingtung County, Taiwan. 16S rRNA gene sequence studies indicated that the novel strain formed a monophyletic branch at the periphery of the evolutionary radiation occupied by the genus Vogesella. Its closest neighbours were Vogesella indigofera ATCC 19706(T) and Vogesella perlucida DS-28(T) (both with 97.4 % gene sequence similarity). The novel isolate could be distinguished from these species by several phenotypic characteristics. The predominant fatty acids were summed feature 3 (C(16 : 1)omega7c and/or C(15 : 0) iso 2-OH; 60 %), C(16 : 0) (13.6 %) and C(18 : 1)omega7c (12.5 %). The DNA G+C content of strain GR13(T) was 63 mol%. The DNA-DNA hybridization values for the novel strain with V. indigofera and V. perlucida were <25 %. On the basis of the 16S rRNA gene sequence analysis and the chemotaxonomic and physiological data, it is concluded that strain GR13(T) represents a novel species in the genus Vogesella, for which the name Vogesella lacus sp. nov. is proposed. The type strain is GR13(T) (=BCRC 17836(T)=LMG 24504(T)).

Belliella pelovolcani sp. nov., isolated from a mud-volcano in Taiwan.

Strain CC-SAL-25(T), a non-motile, Gram-negative, red-pigmented bacterium, was isolated from a rare mud-volcano, located in Wandan, Pingtung County, Taiwan. Studies based on 16S rRNA gene sequences showed that the strain clustered closely with Belliella baltica BA143(T) (95.4 % sequence similarity). A menaquinone with seven isoprene units (MK-7) was the major respiratory quinone. The fatty acid profile was slightly different from that of B. baltica BA143(T). The results of the physiological and biochemical tests showed that strain CC-SAL-25(T) could be clearly differentiated from recognized Belliella species based on phenotypic properties. It was evident from the genotypic and phenotypic data that strain CC-SAL-25(T) should be classified as representing a second novel species in the genus Belliella. The name proposed for this taxon is Belliella pelovolcani sp. nov., and the type strain is CC-SAL-25(T) (=BCRC 17883(T)=KCTC 13248(T)).

Flectobacillus roseus sp. nov., isolated from freshwater in Taiwan.

Two Gram-negative, aerobic, pale pink/rose-coloured, rod-shaped, non-motile bacterial strains, designated GFA-11(T) and RG-4, were isolated from a freshwater fish culture pond and a freshwater spring sample, respectively. Based on characterization by using a polyphasic approach, the two strains showed highly similar phenotypic, physiological and genetic characteristics. They shared 99.9 % 16S rRNA gene sequence similarity and 89-94 % DNA-DNA relatedness, suggesting that they represent a single genomic species. Phylogenetic analysis based on 16S rRNA gene sequences showed that strains GFA-11(T) and RG-4 formed a monophyletic branch at the periphery of the evolutionary radiation occupied by the genus Flectobacillus within the family Flexibacteraceae. Their closest neighbours were Flectobacillus major DSM 103(T) (97.7 % 16S rRNA gene sequence similarity) and Flectobacillus lacus CL-GP79(T) (95.9 %). Levels of DNA-DNA relatedness between the two novel strains and the type strains of F. major and F. lacus were less than 70 %. The results of physiological and biochemical tests allowed clear phenotypic differentiation of strains GFA-11(T) and RG-4 from recognized members of the genus Flectobacillus. The predominant fatty acid constituents of strain GFA-11(T) were C(16 : 1)omega5c (40.2 % of the total) and iso-C(15 : 0) (15.0 %). The DNA G+C content of strain GFA-11(T) was 39.7 mol%. On the basis of 16S rRNA gene sequence analysis and chemotaxonomic and physiological data, strains GFA-11(T) and RG-4 are considered to represent a novel species of the genus Flectobacillus, for which the name Flectobacillus roseus sp. nov. is proposed. The type strain is GFA-11(T) (=BCRC 17834(T)=LMG 24501(T)).

Andreprevotia lacus sp. nov., isolated from a fish-culture pond.

A bacterial strain designated GFC-1(T) was isolated from a fish-culture pond in Taiwan and was characterized by using the polyphasic taxonomic approach. Strain GFC-1(T) was Gram-negative, aerobic, rod-shaped, motile and non-spore-forming. Phylogenetic analyses based on 16S rRNA gene sequences showed that the strain belonged to the genus Andreprevotia of the family Neisseriaceae and its closest neighbour was Andreprevotia chitinilytica JS11-7(T) (97.0 % sequence similarity). The results of physiological and biochemical tests allowed clear phenotypic differentiation of isolate GFC-1(T) from A. chitinilytica JS11-7(T). The major fatty acids were summed feature 3 (C(16 : 1)omega7c and/or iso-C(15 : 0) 2-OH), C(16 : 0) and C(18 : 1)omega7c. The DNA G+C content was 63.0 mol%. On the basis of 16S rRNA gene sequence analysis and chemotaxonomic and physiological data, strain GFC-1(T) should be classified as representing a novel species and a second member of the genus Andreprevotia, for which the name Andreprevotia lacus sp. nov. is proposed. The type strain is GFC-1(T) (=BCRC 17832(T)=LMG 24502(T)).

Vogesella perlucida sp. nov., a non-pigmented bacterium isolated from spring water.

A transparent, non-pigmented, Gram-negative, rod-shaped bacterium, designated strain DS-28(T), was isolated from water samples collected from a spring located in Tainan County, Taiwan. 16S rRNA gene sequence analysis indicated that the novel strain formed a monophyletic branch at the periphery of the evolutionary radiation occupied by the genus Vogesella; the only sole close neighbour of the novel strain was Vogesella indigofera ATCC 19706(T) (97.4 % 16S rRNA gene sequence similarity). The isolate was distinguished from V. indigofera on the basis of genotypic data, several phenotypic properties and an inability to produce characteristic blue-pigmented colonies on peptone agar. The fatty acid profile was slightly different from that reported for V. indigofera ATCC 19706(T). It was evident from the genotypic and phenotypic data that strain DS-28(T) represents a novel species of the genus Vogesella, for which the name Vogesella perlucida sp. nov. is proposed. The type strain is DS-28(T) (=BCRC 17730(T)=LMG 24214(T)).

Tenacibaculum aiptasiae sp. nov., isolated from a sea anemone Aiptasia pulchella.

A novel bacterial strain, designated a4T, isolated from a sea anemone (Aiptasia pulchella) in Taiwan, was characterized using a polyphasic taxonomic approach. Strain a4T was aerobic, Gram-negative, pale-yellow-pigmented and rod-shaped. It grew optimally at 30-35 degrees C, in the presence of 3-4 % (w/v) NaCl and at pH 8.0. Phylogenetic analyses based on 16S rRNA gene sequences showed that the strain belonged to the genus Tenacibaculum (family Flavobacteriaceae, phylum Bacteroidetes). The closest neighbours were Tenacibaculum lutimaris TF-26T (97.6 % similarity) and Tenacibaculum aestuarii SMK-4T (97.7 % similarity). The novel isolate could be distinguished from all Tenacibaculum species by several phenotypic characteristics. The major fatty acids were summed feature 3 (comprising C16 : 1 omega 7c and/or iso-C15 : 0 2-OH, 19.6 %), iso-C15 : 0 (12.9 %), iso-C16 : 0 3-OH (10.2 %), iso-C17 : 0 3-OH (9.9 %) and iso-C15 : 1 (9.5 %). The DNA G+C content was 35.0 mol%. Hence, genotypic and phenotypic data demonstrate that strain a4(T) should be classified as a representative of a novel species in the genus Tenacibaculum, for which the name Tenacibaculum aiptasiae sp. nov. is proposed. The type strain is a4T (=BCRC 17655T =LMG 24004T).

Azonexus hydrophilus sp. nov., a nifH gene-harbouring bacterium isolated from freshwater.

Three Gram-negative, non-pigmented, rod-shaped, facultatively aerobic bacterial strains, designated d8-1T, d8-2 and IMCC1716, were isolated from a freshwater spring sample and a eutrophic freshwater pond. Based on characterization using a polyphasic approach, the three strains showed highly similar phenotypic, physiological and genetic characteristics. All of the strains harboured the nitrogenase gene nifH, but nitrogen-fixing activities could not be detected in nitrogen-free culture media. The three strains shared 99.6-99.7 % 16S rRNA gene sequence similarity and showed 89-100 % DNA-DNA relatedness, suggesting that they represent a single genomic species. Phylogenetic analysis based on 16S rRNA gene sequences showed that strains d8-1T, d8-2 and IMCC1716 formed a monophyletic branch in the periphery of the evolutionary radiation occupied by the genus Azonexus. Their closest neighbours were Azonexus caeni Slu-05T (96.7-96.8 % similarity) and Azonexus fungiphilus BS5-8T (96.3-96.6 %). The DNA-DNA relatedness of the novel strains to these two species of the genus Azonexus was less than 70 %. The isolates could also be differentiated from recognized members of the genus Azonexus on the basis of phenotypic and biochemical characteristics. It is evident, therefore, that the three strains represent a novel species of the genus Azonexus, for which the name Azonexus hydrophilus sp. nov. is proposed. The type strain is d8-1T (=LMG 24005T=BCRC 17657T).

Pseudogulbenkiania subflava gen. nov., sp. nov., isolated from a cold spring.

A yellow-coloured bacterial strain, designated BP-5(T), was isolated from a water sample of a cold spring located in the Hsinchu area of northern Taiwan. Cells of the strain were Gram-negative, non-spore-forming rods with a polar flagellum. The isolate was able to grow at 15-42 degrees C, 0-1 % NaCl and pH 6-8. The predominant fatty acids were summed feature 3 (C(16 : 1)omega7c and/or iso-C(15 : 0) 2-OH), C(16 : 0) and C(18 : 1)omega7c. The major respiratory quinone was ubiquinone 8. The DNA G+C content was 63.2 mol%. 16S rRNA gene sequence analysis indicated that strain BP-5(T) belonged to the class Betaproteobacteria and was a member of the family Neisseriaceae. Its closest phylogenetic neighbours were Gulbenkiania mobilis E4FC31(T) (95.0 % 16S rRNA gene sequence similarity), Chromobacterium subtsugae PRAA4-1(T) (95.0 %), Chromobacterium violaceum ATCC 12472(T) (94.3 %), Vogesella indigofera ATCC 19706(T) (93.8 %) and Aquitalea magnusonii TRO-001DR8(T) (93.7 %). On the basis of the evidence from this polyphasic study, strain BP-5(T) is considered to represent a novel species of a new genus, for which the name Pseudogulbenkiania subflava gen. nov., sp. nov. is proposed. The type strain of Pseudogulbenkiania subflava is BP-5(T) (=BCRC 17727(T) =LMG 24211(T)).

Luteimonas aquatica sp. nov., isolated from fresh water from Southern Taiwan.

A yellow-pigmented bacterial strain, designated RIB1-20(T), isolated from fresh water was investigated by means of a polyphasic taxonomic approach. The cells were Gram-negative, rod-shaped and non-spore-forming. Phylogenetic analyses with the 16S rRNA gene sequence showed that the strain formed a monophyletic branch towards the periphery of the evolutionary radiation occupied by the genus Luteimonas, its two closest neighbours being Luteimonas composti CC-YY255(T) (96.1% sequence similarity) and Luteimonas mephitis B1953/27.1(T) (95.8%). Strain RIB1-20(T) was clearly distinguished from both of those type strains using phylogenetic analysis, DNA-DNA hybridization, fatty acid composition data and a range of physiological and biochemical characteristics. It is evident from the genotypic and phenotypic data that strain RIB1-20(T) represents a novel species of the genus Luteimonas, for which the name Luteimonas aquatica sp. nov. is proposed. The type strain is RIB1-20(T) (=BCRC 17731(T) =LMG 24212(T)).