Sphingosinicella ginsenosidimutans sp. nov., with ginsenoside converting activity

Genomic-based taxonomic classification of the order Sphingomonadales

The order Sphingomonadales strains are globally distributed in various biomes and are renowned for their biodegradable and biosynthesis capabilities. At present, it consists of 4 families and 49 genera making it the third largest order within the class Alphaproteobacteria. However, their taxonomy remains complex, especially due to polyphyly in the family Sphingomonadaceae. In this study, we collected 429 Sphingomonadales type strain genomes, reconstructed robust phylogenomic relationships, and proposed delineation thresholds at the genus and family levels based on average amino acid identities (AAI) and evolutionary distances (ED). Based on the maximum-likelihood and Bayesian phylogenomic trees reconstructed by two molecular sets determined by orthologous sequence identity and the Genome Taxonomy Database, the consensus degree values were all higher than 90%, revealing that those phylogenomic trees had similar topological structures. By confirming monophyletic taxa and determining stable nodes, we reclassified the order Sphingomonadales into thirteen families including nine novel ones. AAI calculations indicated that the average intra-family AAI values ranged from 0.62 to 0.84, while inter-family ones were 0.51 to 0.60. ED summaries demonstrated that the average and median intra-family ED values were 0.16 to 0.57, and inter-family ones ranged from 0.50 to 1.22. Comparisons of AAI and ED values calculated by using genomic and phylogenetic analyses supported that those 13 families were significantly separated with p values < 2.2×10-16. Thus, it was speculated that the AAI and ED thresholds for distinguishing different families were <0.6 and >0.5, respectively. Additionally, we reclassified 163 species into new genera with their phylogenetic topologies, according to the previous genus AAI and ED boundaries of 0.7 and 0.4. Our study is the first genomic-based study of the order Sphingomonadales and will promote further insights into the evolution of this order.

Sphingosinicella rhizophila sp. nov., Isolated from Oat (Avena sativa L.) Rhizosphere Soil

A Gram-stain-negative, aerobic, rod-shaped, and yellow-colored bacterium, designated strain GR2756T, was isolated from a rhizosphere soil sample of oat (Avena sativa L.). The strain GR2756T was able to grow at 15-35 °C, pH 6.0-8.0, and 0-1.5 % (w/v) NaCl concentration. Phylogenetic analysis based on 16S rRNA gene sequences indicated that the strain GR2756T was clustered with Sphingosinicella vermicomposti YC7378T (95.7 %), Sphingosinicella humi QZX222T (95.6 %), and Sphingomonas montis DRJ-4T (95.5 %). Strain GR2756T contained ubiquinone Q-10 and homospermidine as the major respiratory quinone system and polyamine, respectively. The major fatty acids detected from strain GR2756T were C16:0, Summed Feature 3 (C16:1 ω7c and/or C16:1 ω6c), and Summed Feature 8 (C18:1 ω7c and/or C18:1 ω6c), C17:1 ω6c and C16:0 2-OH. The major polar lipids are phosphatidylethanolamine (PE), phospholipid, glycolipid, and unidentified polar lipid. The genomic DNA G+C was 63.2%. Between the strains GR2756T and S. humi CCTCC AB 2018030T, the ANI and dDDH values were lower than the proposed and generally accepted species boundaries. On the basis of phenotypic, genotypic, and phylogenetic analysis, strain GR2756T represents a novel species of the genus Sphingosinicella, for which the name Sphingosinicella rhizophila sp. nov. is proposed. The type strain of the proposed new taxon is strain GR2756T (= CCTCC AB 2023102T = CGMCC 1.61580T = NBRC 116723T).

Sphingosinicella flava sp. nov., indole acetic acid producing bacteria isolated from maize field soil

A novel isolated yellow-pigmented bacterial designated strain UDD2^T was isolated from a maize field soil sample collected in Ilsan, Republic of Korea. Cells of strain UDD2^T were Gram-stain-negative, non-sporulating, long rod-shaped and exhibited flagellar motility. Cells could grow at 15-42 °C and pH 5.5-11.0. Strain UDD2^T was sensitive to NaCl and barely tolerated up to 1 % NaCl (w/v). Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain UDD2^T formed a separate clade with the members of genus Sphingosinicella within the family Sphingomonadaceae. Strain UDD2^T showed the highest 16S rRNA gene sequence similarity to Sphingosinicella vermicomposti KCTC 224446^T (98.5 %) and Sphingosinicella humi KCTC 62519^T (96.7 %), followed by members of the genus Sphingomonas (96.4-94.5 %) and Sphingobium (96.1-94.9 %), but they were located in other phylogenetic clusters. Average nucleotide identity and digital DNA-DNA hybridization values between strain UDD2^T and S. vermicomposti KCTC 224446^T and S. humi KCTC 62519^T were 80.2/24.2 and 75.6/20.4 %, respectively. The total size of the genome was 2 421 697 bp and composed of one circular chromosome, with a G+C content of 63.7 mol%. Strain UDD2^T produced indole acetic acid (IAA) in the presence of l-tryptophan. Bacterial IAA is a crucial phytohormone in plant growth and development. Gene clusters for indole-3-glycerol phosphate synthase and tryptophan synthase were found in the genome of strain UDD2^T. To the best of our knowledge, no member of the genus Sphingosinicella has been reported to produce IAA to date. The major cellular fatty acids (>10 %) were found to be C_16 : 0, C_14 : 0 2OH and summed feature 3 (comprising C_{16  : 1} ω7c and/or iso-C_{15  :  0} 2-OH). Strain UDD2^T had ubiquinone Q-10 as the major respiratory quinone and homospermidine as the major polyamine. The polar lipids were diphosphatidylglycerol, phosphatidylethanolamine, sphingoglycolipid, phosphatidylglycerol, phosphatidylcholine, three unidentified phosphoglycolipids, one unidentified phospholipid, one unidentified aminoglycophospholipid, one unidentified glycolipid and one unidentified polar lipid. Based on the phylogenetic, phenotypic, chemotaxonomic and genotypic data, strain UDD2^T represents a novel species of the genus Sphingosinicella, for which the name Sphingosinicella flava is proposed. The type strain is UDD2^T (=KCTC 82357^T=NBRC 114507^T).

Isolation, characterisation and genome analysis of a novel ginsenosides hydrolysing bacterium Ginsengibacter hankyongi gen. nov., sp. nov. isolated from soil

A novel yellow-pigmented bacterial strain (designated BR5-29^T), was isolated and its taxonomy was studied. Phylogenetic study based on the 16S rRNA and draft genome sequence placed the strain BR5-29^T in a distinct lineage within the family Chitinophagaceae, sharing ≤ 93.4% sequence similarity with members of the closely related genera Ferruginibacter, Flavisolibacter, Flavitalea and Niastella. The novel isolate showed the highest sequence similarity to the genus Ferruginibacter. The draft genome of strain BR5-29^T had a total length of 5,505,520 base pairs. A total of 4585 genes were identified, in which 4537 were CDS and 48 RNA genes were assigned a putative function. The genome annotation of BR5-29^T showed 225 carbohydrate genes which may be responsible for the conversion of major ginsenosides to minor ginsenosides. Strain BR5-29^T contained MK-7 as a predominant quinone, and iso-C_15:0, iso-C_15:0 G, iso-C_17:0 3-OH, and C_16:1 ω7c and/or C_16:1 ω6c (summed feature 3) as major fatty acids. The polar lipids found in the strain BR5-29^T were phosphatidylglycerol (PG), diphosphatidylglycerol (DPG), phosphatidylethanolamine (PE), five unidentified polar lipids (L1-L5), two unidentified aminolipid and one unidentified aminophospholipid. Our pilot data demonstrate that the novel isolate shares the similar major polar lipid PE, major quinone MK-7 and major fatty acids with the described members of the family Chitinophagaceae. However, the low 16S rRNA gene sequence (< 93.4%), the little high amount of C_12:0, iso-C_17:0 2-OH and iso-C_15:1 2-OH fatty acids, low DNA G + C content, and the presence of DPG, PG and two unidentified polar lipids (L1 and L3 differentiate the BR5-29^T from its closest phylogenetic neighbors. Thus, the isolate represents a novel genus and species in the family Chitinophagaceae for which the name Ginsengibacter hankyongi gen. nov., sp. nov. is proposed. The type strain is BR5-29^T (= KACC 19446^T = LMG 30462^T). Thus, we predict that this novel strain may prove useful for the future research analysis (target gene cloning) and mass production of Rg3.

Luteimonas granuli sp. nov., Isolated from Granules of the Wastewater Treatment Plant

A Gram-reaction negative, aerobic, non-motile, light yellow colored, and rod-shaped bacterium (designated Gr-4^T) isolated from granules of a wastewater treatment plant, was characterized by a polyphasic approach to clarify its taxonomic position. Strain Gr-4^T was observed to grew optimally at 30 ºC and at pH 7.0 on R2A medium. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain Gr-4^T belongs to the genus Luteimonas of the family Xanthomonadaceae and was most closely related to Luteimonas padinae CDR SL 15^T (99.1%), Luteimonas terricola DSM 22344^T (98.5%) and Luteimonas arsenica 26-35^T (97.6). The genome comprises 2,917,404 bp with a G+C content of 70.5 mol%. The ANI value between strain Gr-4^T and Luteimonas padinae CDR SL 15^T was 87.3%. The DNA-DNA relatedness value between strain Gr-4^T and Luteimonas padinae CDR SL 15^T, Luteimonas terricola DSM 22344^T was 36.4 ± 1.3% and 14.2 ± 1.7%, respectively. The predominant quinone was Q-8. The major fatty acids were iso-C_15:0, iso-C_16:0 and summed feature 9 (comprising iso-C_17:1ω9c and/or C_16:0 10-methyl) supported the affiliation of strain Gr-4^T to the genus Luteimonas. Moreover, the physiological, biochemical results, and low level of ANI and DNA-DNA relatedness value allowed the phenotypic and genotypic differentiation of strains Gr-4^T from other Luteimonas species with validly published names. The novel isolate therefore represents a novel species, for which the name Luteimonas granuli sp. nov. is proposed, with the type strain Gr-4^T (=KACC 16614^T = JCM 18203^T).

Hankyongella ginsenosidimutans gen. nov., sp. nov., isolated from mineral water with ginsenoside coverting activity

In this study, a novel ginsenoside transforming bacterium, strain W1-2-3^T, was isolated from mineral water. The 16S rRNA gene sequence analysis showed that strain W1-2-3^T shares 93.7-92.2% sequence similarity with the members of the family Sphingomonadaceae and makes a group with Sphingoaurantiacus capsulatus YLT33^T (93.7%) and S. polygranulatus MC 3718^T (93.4%). The novel isolate efficiently hydrolyses the ginsenoside Rc to Rd. The genome comprises a single circular 2,880,809, bp chromosome with 3211 genes in total, and 1993 protein coding genes. The isolate was observed to grow at 10-37 °C and at pH 6-10 on R2A agar medium; maximum growth was found to occur at 25 °C and pH 7.0. Strain W1-2-3^T was found to contain ubiquinone-10 as the predominant quinone and the fatty acids C_16:1, C_17:1ω6c, C_14:0 2-OH, summed feature 3 (C_16:1ω6c/C_16:1ω7c) and summed feature 8 (C₁₈:₁ω6c/C_18:1ω7c). The DNA G+C content was determined to be 65.9 mol%. Strain W1-2-3^T can be distinguished from the other members of the family Sphingomonadaceae by a number of chemotaxonomic and phenotypic characteristics. The major polar lipids of strain W1-2-3^T were identified as phosphatidylethanolamine, an unidentified glycolipid and an unidentified polar lipid. The major poly amine was found to be homospermidine. Based on polyphasic taxonomic analysis, strain W1-2-3^T is concluded to represent a novel species within a new genus, for which the name Hankyongella ginsenosidimutans gen. nov., sp. nov. is proposed. The type strain of Hankyongella ginsenosidimutans is W1-2-3^T (= KACC 18307^T = LMG 28594^T).

Corallincola spongiicola sp. nov., isolated from sponge

A gram-negative, motile, strictly aerobic, and rod-shaped bacterium designated 176GS2-150^T was isolated from the sponge Hymeniacidon sinapium. The taxonomic position of the novel isolate was confirmed using the polyphasic approach. Strain 176GS2-150^T grew well at 25 °C on marine agar. Based on its 16S rRNA gene sequence, we showed that strain 176GS2-150^T belongs to the family Psychromonadaceae and class Gammaproteobacteria and is related to Corallincola platygyrae JLT2006^T (96.84% sequence similarity). The G + C content of the genomic DNA was 49.0 mol%. The assembled draft genome of strain 176GS2-150^T was 4.2 Mbp and consisted of 14 contigs. The major respiratory quinone was Q-8, and the major fatty acids were summed feature 3 (comprising C_16 :1ω6c and/or C_16:1ω7c), summed feature 8 (comprising C_18 :1ω7c and/or C_18:1ω6c), C_17:0 iso, C_16:0, and C_15:0 iso. The polar lipids were phosphatidylglycerol, phosphatidylethanolamine, 3 unidentified phospholipids, and 1 unidentified polar lipid. On the basis of the genotypic and phenotypic characteristics, strain 176GS2-150^T can be placed as a new species within the genus Corallincola; the name Corallincola spongiicola sp. nov. has been proposed, with type strain 176GS2-150^T (= KACC 19890^T = LMG 31317^T).

Olivibacter ginsenosidimutans sp nov., with ginsenoside converting activity isolated from compost, and reclassification of Pseudosphingobacterium domesticum as Olivibacter domesticus comb. nov

A Gram-stain-negative, aerobic and rod-shaped, bacterium designated as strain BS18^T, was isolated from compost and subjected to a polyphasic taxonomic analysis. On the basis of the results of 16S rRNA gene sequence analysis, BS18^T represents a member of the genus Olivibacter of the family Sphingobacteriaceaeand is most closely related to Olivibacter oleidegradansTBF2/20.2^T (93.7 %), Olivibacter jilunii 14-2A^T (93.6 %), Olivibacter ginsengisoli Gsoil 060^T (93.6 %), Pseudosphingobacterium domesticumDC186^T (93.0 %) and shared ≤93.1 % sequence similarity with the other members of the genus Olivibacter. BS18^T contained MK-7 as the predominant quinone, iso-C15 : 0, iso-C17 : 0 3-OH and summed feature 4 (iso-C15 : 0 2-OH and/or C16 : 1ω7c), as the major fatty acids and phosphatidylethanolamine (PE) as main polar lipid. BS18^T could be distinguished from the other members of the genus Olivibacter by a number of chemotaxonomic and phenotypic characteristics. On the basis of the results of polyphasic taxonomic analysis, BS18^T represents a novel species within the genus, for which the name Olivibacter ginsenosidimutans sp. nov. is proposed. The type strain of Olivibacter ginsenosidimutans is BS18^T (=KACC 16612^T=JCM 18200^T). It is also proposed to transfer Pseudosphingobacterium domesticumto the genus Olivibacter, as Olivibacter domesticus comb. nov. (type strain DC186^T=CCUG 54353^T=LMG 23837^T).

Sphingomonas montis sp. nov., Isolated from Forest Soil of Low-Altitude Mountain

Strain DRJ-4^T was isolated from forest soil of a low-altitude mountain and was taxonomically characterized by a polyphasic approach. This strain was yellow-colored, Gram-stain-negative, strictly aerobic, motile, non-sporulating, catalase-positive, oxidase-negative, and rod-shaped. Strain DRJ-4^T was able to grow at 20-42 °C, pH 6.5-10.0, and 0-1.0% (w/v) NaCl concentration. Based on the 16S rRNA gene sequence analysis, strain DRJ-4^T formed a distinct lineage within the members of the family Sphingomonadaceae of the phylum Proteobacteria and moderately related to Sphingomonas faucium E62-3^T (96.67% sequence similarity), 'Sphingosinicella ginsenosidimutans' BS11 (96.45% sequence similarity), Sphingosinicella vermicomposti YC7378^T (96.27% sequence similarity), and Sphingobium boeckii 469^T (95.82% sequence similarity). The sole respiratory quinone was ubiquinone Q-10 and the major polyamine was homospermidine. The polar lipid profile revealed the presence of phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol, phosphatidylcholine, phosphatidylmonomethylethanolamine, and sphingoglycolipid. The predominant fatty acids of strain DRJ-4^T were summed feature 8 (C_18:1ω7c and/or C_18:1ω6c), summed feature 3 (C_16:1ω7c and/or C_16:1ω6c), C_16:0, and C_17:1ω6c. The genomic DNA G + C was 64.0 mol %. On the basis of phenotypic, genotypic, and phylogenetic analysis, strain DRJ-4^T represents a novel species of the genus Sphingomonas, for which the name Sphingomonas montis sp. nov. is proposed. The type strain of Sphingomonas montis is DRJ-4^T (= KEMB 9005-708^T = NBRC 113142^T).

Tardibacter chloracetimidivorans gen. nov., sp. nov., a novel member of the family Sphingomonadaceae isolated from an agricultural soil from Jeju Island in Republic of Korea

A pale yellow bacterial strain, designated JJ-A5^T, was isolated form an agricultural soil from Jeju Island in Republic of Korea. Cells of the strain were Gram-stain-negative, motile, flagellated and rod-shaped. The strain grew at 15-30°C, pH 6.0-9.0, and in the presence of 0-1.5% (w/v) NaCl. Growth occurred on R2A, but not on Luria-Bertani agar, nutrient agar, trypticase soy agar and MacConkey agar. The strain utilized alachlor as a sole carbon source for growth. The strain JJ-A5^T showed 16S rRNA gene sequence similarities lower than 95.4% with members of the family Sphingomonadaceae. Phylogenetic analysis showed that the strain belongs to the family Sphingomonadaceae and strain JJ-A5^T was distinctly separated from established genera of this family. The strain contained Q-10 as dominant ubiquinone and spermidine as major polyamine. The predominant cellular fatty acids were summed feature 8 (C_18:1ω7c and/or C_18:1ω6c), summed feature 3 (C_16:1ω7c and/or C_16:1ω6c), 11-methyl C_18:1ω7c, C_16:0 and C_14:0 2-OH. The major polar lipids were phosphatidylethanolamine, phosphatidylglycerol, sphingoglycolipid, and phosphatidylcholine. The DNA G + C content of the strain was 62.7 mol%. On the basis of the phenotypic, genomic and chemotaxonomic characteristics, strain JJ-A5^T is considered to represent a novel genus and species within the family Sphingomonadaceae, for which the name Tardibacter chloracetimidivorans gen. nov., sp. nov. is proposed. The type strain of Tardibacter chloracetimidivorans is JJ-A5^T (= KACC 19450^T = NBRC 113160^T).

Bacillus spongiae sp. nov., isolated from sponge of Jeju Island

A Gram-reaction-positive, strictly aerobic, motile, endospore- forming, and rod-shaped bacterial strain designated 135PIL107-10^T was isolated from a sponge on Jeju Island, and its taxonomic position was investigated using a polyphasic approach. Strain 135PIL107-10^T grew at 20-37°C (optimum temperature, 25°C) and pH 6.0-10.0 (optimum pH, 6.0) on marine and R2A agars. Based on 16S rRNA gene phylogeny analysis, the novel strain formed a new branch within the genus Bacillus of the family Bacillaceae, and formed clusters with Bacillus thaohiensis NHI-38^T (96.8%), Bacillus fengqiuensis NPK15^T (96.7%), and Bacillus songklensis CAU 1033^T (96.7%). Lower sequence similarities (97.0%) were found with the type strains of all other recognized members of the genus Bacillus (95.6-96.8% similarity). The G + C content of the genomic DNA was 43.6 mol%. The predominant respiratory quinone was menaquinone-7 and the major fatty acids were iso-C_15:0 and iso-C_17:1ω10c. The overall polar lipid patterns were diphosphatidylglycerol, phosphatidylglycerol, and phosphatidylethanolamine. The diagnostic diamino acid in the cell-wall peptidoglycan was meso-diaminopimelic acid. The isolate therefore represents a novel species, for which the name Bacillus spongiae sp. nov. is proposed, with the type strain 135PIL107-10^T (= KACC 19275^T = LMG 30080^T).

Aquimarina spongiicola sp. nov., isolated from spongin

A Gram-reaction-negative, aerobic, motile by gliding, non-spore-forming, rod-shaped bacterial strain, designated 122CH820-2^T, was isolated from spongin. This bacterium was characterized to determine its taxonomic position by using a polyphasic approach. Strain 122CH820-2^T grew well at 25-30 °C on marine agar. On the basis of 16S rRNA gene sequence similarity, strain 122CH820-2^T belonged to the family Flavobacteriaceae and was closely related to Aquimarina mytili PSC33^T (96.8 % sequence similarity) and A. penaei P3-1^T (96.7 %). Lower sequence similarities (<96.5 %) were found with all of the other recognized members of the genus Aquimarina. The G+C content of the genomic DNA was 35.2 mol%. The major respiratory quinone was menaquinone MK-6 and the major fatty acids were C15 : 0, iso-C17 : 0 3-OH, iso-C15 : 1 G and iso-C15 : 0 3-OH. The polar lipids were phosphatidylethanolamine, one aminophospholipid and five unidentified polar lipids. Strain 122CH820-2^T could be differentiated genotypically and phenotypically from recognized species of the genus Aquimarina. The isolate therefore represents a novel species, for which the name Aquimarina spongiicola sp. nov. is proposed, with the type strain 122CH820-2^T (=KACC 19274^T=LMG 30078^T).

Paraburkholderia azotifigens sp. nov., a nitrogen-fixing bacterium isolated from paddy soil

A Gram-stain-negative, aerobic, non-motile and rod-shaped bacterial strain, designated NF2-5-3^T, was isolated from a paddy soil in Anseong city, Republic of Korea. This bacterium was characterized to determine its taxonomic position using a polyphasic approach. On the basis of 16S rRNA gene sequence analysis, strain NF2-5-3^T had a close relationship with, and was related most closely to, members of the genus Paraburkholderia, namely Paraburkholderia caribensis MWAP64^T (98.8 % similarity), P. sabiae Br3407^T (98.8 %), P. hospita LMG 20598^T (98.5 %), P. terrae NBRC 100964^T (98.3 %) and P. phymatum STM815^T (98.1 %). Growth of strain NF2-5-3^T occurred at 15-37 °C, at pH 6.0-8.0 and at NaCl concentrations of 0-2 % (w/v). The major respiratory quinone was ubiquinone 8 (Q-8) and the major fatty acids were C16 : 0, summed feature 8 (comprising C18 : 1ω7c and/or C18 : 1ω6c), C17 : 0 cyclo and C16 : 0 3-OH. The polar lipid profile consisted of phosphatidylglycerol, diphosphatidylglycerol, phosphatidylethanolamine, an unidentified phospholipid, unidentified aminophospholipids, unidentified aminolipids and unidentified polar lipids. The G+C content of the genomic DNA was 64.2 mol%. DNA-DNA relatedness values between strain NF2-5-3^T and its closest phylogenetic neighbours were much lower than 70 %. Strain NF2-5-3^T could be differentiated phylogenetically and phenotypically from recognized species of the genus Paraburkholderia. The isolate therefore represents a novel species, for which the name Paraburkholderia azotifigens sp. nov. is proposed, with NF2-5-3^T (=KACC 18968^T=LMG 29961^T) as the type strain.

Mucilaginibacter ginsenosidivorans sp. nov., Isolated from Soil of Ginseng Field

A Gram-reaction-negative, aerobic, nonmotile, nonspore-forming, and rod-shaped bacterial strain designated Gsoil 3017^T was isolated from soil of ginseng field and investigated by phenotypic and phylogenetic analyses. Strain Gsoil 3017^T grew at 10-37 °C (optimal growth at 30 °C) and at pH 5.5-8.0 (optimal growth at pH 7) on R2A and nutrient agar without additional NaCl as a supplement. Strain Gsoil 3017^T possessed β-glucosidase activity, which was responsible for its ability to transform ginsenosides Rb₁, Rc, and Rd (the three dominant active components of ginseng) to F₂ and C-K, respectively. Based on 16S rRNA gene phylogeny, the novel strain represents a new branch within the genus Mucilaginibacter family Sphingobacteriaceae, and clusters with Mucilaginibacter frigoritolerans FT22^T (95.6%) and Mucilaginibacter gotjawali SA3-7^T (95.6%). The G+C content of the genomic DNA was 48.7%. The predominant respiratory quinone was MK-7, and the major fatty acids were iso-C_15:0, iso-C_17:0 3-OH, and summed feature 3 (comprising C_16:1 ω6c and/or C_16:1 ω7c). The major polar lipid was phosphatidylethanolamine. Strain Gsoil 3017^T could be differentiated genotypically and phenotypically from other type strains of the genus Mucilaginibacter. The isolate therefore represents a novel species, for which the name Mucilaginibacter ginsenosidivorans sp. nov. is proposed, with the type strain Gsoil 3017^T (=KACC 14954^T = JCM 17081^T).

Mucilaginibacter ginsenosidivorans sp. nov., Isolated from Soil of Ginseng Field

A Gram-reaction-negative, aerobic, nonmotile, nonspore-forming, and rod-shaped bacterial strain designated Gsoil 3017^T was isolated from soil of ginseng field and investigated by phenotypic and phylogenetic analyses. Strain Gsoil 3017^T grew at 10-37 °C (optimal growth at 30 °C) and at pH 5.5-8.0 (optimal growth at pH 7) on R2A and nutrient agar without additional NaCl as a supplement. Strain Gsoil 3017^T possessed β-glucosidase activity, which was responsible for its ability to transform ginsenosides Rb₁, Rc, and Rd (the three dominant active components of ginseng) to F₂ and C-K, respectively. Based on 16S rRNA gene phylogeny, the novel strain represents a new branch within the genus Mucilaginibacter family Sphingobacteriaceae, and clusters with Mucilaginibacter frigoritolerans FT22^T (95.6%) and Mucilaginibacter gotjawali SA3-7^T (95.6%). The G+C content of the genomic DNA was 48.7%. The predominant respiratory quinone was MK-7, and the major fatty acids were iso-C_15:0, iso-C_17:0 3-OH, and summed feature 3 (comprising C_16:1 ω6c and/or C_16:1 ω7c). The major polar lipid was phosphatidylethanolamine. Strain Gsoil 3017^T could be differentiated genotypically and phenotypically from other type strains of the genus Mucilaginibacter. The isolate therefore represents a novel species, for which the name Mucilaginibacter ginsenosidivorans sp. nov. is proposed, with the type strain Gsoil 3017^T (=KACC 14954^T = JCM 17081^T).

Daejeonia ginsenosidivorans gen. nov., sp. nov., a ginsenoside-transforming bacterium isolated from lake water

A Gram-stain-negative, oxidase- and catalase-positive, strictly aerobic, non-gliding bacterial strain, designated as NPT, was isolated from lake water and subjected to a taxonomic study using a polyphasic approach. Colonies of strain NP5T were light-yellow-coloured, circular with regular margins, and opaque. Cells were rods, 0.2-0.5 µm wide and 1.2-3.0 µm long. Strain NP5T possessed β-glycosidase activity, which was responsible for its ability to convert ginsenosides Rb1, Rc and Rd (three main active components of ginseng) to ginsenoside F2. Phylogenetic study based on the 16S rRNA gene sequence put strain NP5T in a distinct lineage in the family Flavobacteriaceae, sharing less than 96.0 % sequence similarity with members of the closely related genera Chryseobacterium, Bergeyella, Epilithonimonas and 'Candidatus Amoebinatus'. The novel isolate showed the highest sequence similarity with the genus Chryseobacterium. Strain NP5T contained MK-6 as predominant quinone, and iso-C15 : 0, iso-C17 : 0 3-OH, iso-C16 : 0 3-OH, C18 : 0 3-OH, anteiso-C15 : 0 and C16 : 1ω7c and/or C16 : 1ω6c (summed feature 3) as major fatty acids. The DNA G+C content was 44.8 mol%. The main polar lipids were phosphatidylethanolamine, phosphatidylglycerol and diphosphatidylglycerol. The physiological, biochemical and taxonomical characteristics allowed the phenotypic differentiation of strain NP5T from its closest phylogenetic neighbours. On the basis of the evidence of this polyphasic study, isolate NP5T represents a novel genus and species in the family Flavobacteriaceae for which the name Daejeonia ginsenosidivorans gen. nov., sp. nov. is proposed. The type strain is NP5T (=KACC 18626T=LMG 29198T).

Pseudaminobacter granuli sp. nov., isolated from granules used in a wastewater treatment plant

A Gram negative, aerobic, non-motile and rod-shaped bacterial strain designated as Gr-2^T was isolated from granules used in a wastewater treatment plant in Korea, and its taxonomic position was investigated using a polyphasic approach. Strain Gr-2^T grew at 18-37°C (optimum temperature, 30°C) and a pH of 6.0-8.0 (optimum pH, 7.0) on R2A agar medium. Based on 16S rRNA gene phylogeny, the novel strain showed a new branch within the genus Pseudaminobacter of the family Phyllobacteriaceae, and formed clusters with Pseudaminobacter defluvii THI 051^T (98.9%) and Pseudaminobacter salicylatoxidans BN12^T (98.7%). The G+C content of the genomic DNA was 63.6%. The predominant respiratory quinone was ubiquinone-10 (Q-10) and the major fatty acids were cyclo-C_19:0 ω8c, C_18:1 ω7c, and iso-C_17:0. The overall polar lipid patterns of Gr-2^T were similar to those determined for the other Pseudaminobacter species. DNA-DNA relatedness values between strain Gr-2^T and its closest phylogenetically neighbors were below 18%. Strain Gr-2^T could be differentiated genotypically and phenotypically from the recognized species of the genus Pseudaminobacter. The isolate therefore represents a novel species, for which the name Pseudaminobacter granuli sp. nov. is proposed with the type strain Gr-2^T (=KACC 18877^T =LMG 29567^T).

Mucilaginibacter hankyongensis sp. nov., isolated from soil of ginseng field Baekdu Mountain

A Gram-negative, non-motile, aerobic, and rod-shaped bacterial strain designated as BR5-28^T was isolated from the soil of a ginseng field at Baekdu Mountain Korea, and its taxonomic position was investigated using a polyphasic approach. Strain BR5-28^T grew at 10-42°C (optimum temperature, 30°C) and pH 5.5-8.5 (optimum pH, 7.0) on R2A agar medium without additional NaCl supplementation. Strain BR5- 28T exhibited β-glucosidase activity, which was responsible for its ability to transform the ginsenosides Rb1 and Rd (the two dominant active components of ginseng) to compound-K. Based on 16S rRNA gene phylogeny, the novel strain showed a new branch within the genus Mucilaginibacter of the family Sphingobacteriaceae, and formed clusters with Mucilaginibacter frigoritolerans FT22^T (95.8%) and Mucilaginibacter gotjawali SA3-7^T (95.7%). The G+C content of the genomic DNA was 45.1%. The predominant respiratory quinone was MK-7 and the major fatty acids were summed feature 3 (comprising C_16:1 ω6c and/or C_16:1 ω7c), iso-C_15:0 and anteiso-C_15:0. The major polar lipids were diphosphatidylglycerol, phosphatidylglycerol and phosphatidylethanolamine. Strain BR5-28^T was differentiated genotypically and phenotypically from the recognized species of the genus Mucilaginibacter. The isolate therefore represents a novel species, for which the name Mucilaginibacter hankyongensis sp. nov. is proposed, with the type strain BR5-28^T (=KCTC 22274^T =DSM 21151^T).

Sphingobacterium jejuense sp. nov., with ginsenoside-converting activity, isolated from compost

A Gram-stain-negative, strictly aerobic, non-motile, light yellow, short-rod bacterium (designated GJ30-7T) isolated from compost, was characterized using a polyphasic approach, in order to clarify its taxonomic position. Strain GJ30-7T was observed to grow optimally at 30 °C and at pH 7.0 on R2A agar medium. Strain Gsoil GJ30-7T possessed β-glucosidase activity, which was responsible for its ability to transform ginsenosides Rb1 and Rc (the two main active components of ginseng) to ginsenoside F2. Phylogenetic analysis, based on 16S rRNA gene sequence similarities, indicated that GJ30-7T belongs to the genus Sphingobacterium of the family Sphingobacteriaceae and was most closely related to Sphingobacterium yanglingense JCM 30166T (92.6 %), Sphingobacterium psychroaquaticum KACC 18188T (92.6 %), and Sphingobacterium thermophilum KCTC 23708T (92.0 %). The DNA G+C content was 43 mol% and MK-7 was the major isoprenoid quinone. The main polar lipids were phosphatidylethanolamine, one unidentified phospolipid and one unknown polar lipid. In contrast to standard and reference strains, unidentified sphingolipid was also present. The predominant fatty acids of strain GJ30-7T were iso-C15 : 0, iso-C17 : 0 3-OH, C16 : 1ω7c and/or C16 : 1ω6c (summed feature 3) and iso-C17 : 1ω9c and/or C16 : 0 10-methyl (summed feature 9), supporting the affiliation of strain GJ30-7T to the genus Sphingobacterium. However, strain GJ30-7T could be distinguished genotypically and phenotypically from species of the genus Sphingobacterium with validly published names. The novel isolate therefore represents a novel species, for which the name Sphingobacterium jejuense sp. nov. is proposed, with the type strain GJ30-7T (=KACC 18625T=JCM 30948T).

Compostibacter hankyongensis gen. nov., &nbsp;sp. nov., isolated from compost

A novel bacterial strain, designated strain BS27T, was isolated from mushroom compost and subjected to a taxonomic study using a polyphasic approach. Colonies of BS27T were milky-white, circular with regular fringes and opaque. Cells were short rods, 0.3-0.5 µm wide and 1.2-2.0 µm long. Phylogenetic study based on the 16S rRNA gene sequence placed BS27T in a distinct lineage in the family Chitinophagaceae, sharing 90.1-90.9 % sequence similarity with members of the closely related genera Chitinophaga, Flavitalea, Flavihumibacter, Lacibacter and Flavisolibacter. The novel isolate showed the highest sequence similarities with the members of the genus Chitinophaga. BS27T contained MK-7 as predominant quinone, and iso-C15 : 0, iso-C17 : 0 3-OH, C16 : 1ω7c and/or C16 : 1ω6c (summed feature 3) and iso-C17 : 1I and/or anteiso-C17 : 1B (summed feature 4) as major fatty acids. The DNA G+C content was 53.0 mol%. The major polar lipids of BS27T were phosphatidylethanolamine (PE) and five unidentified polar lipids (L1, L2, L5, L6 and L7). The results of physiological and biochemical tests allowed phenotypic differentiation of BS27T from its closest phylogenetic neighbours. On the basis of the evidence of this polyphasic study, isolate BS27T represents a novel genus and species in the family Chitinophagaceae for which the name Compostibacter hankyongensisgen. nov., sp. nov. is proposed. The type strain is BS27T (=KACC 18745T=JCM 17664T).