Isolation and characterization of a novel glycoside hydrolase positive bacterial strain named Terrimonas ginsenosidimutans sp. nov. with ginsenoside-converting activity.

A novel yellow-pigmented catalase- and oxidase-positive bacterial strain (designated NA20T) was isolated from wetland soil and characterized. Results of 16S rRNA and draft genome sequence analysis placed strain NA20T within the genus Terrimonas of the family Chitinophagaceae. Strain NA20T showed ≤97.1 % sequence similarity to members of the genus Terrimonas and the highest sequence similarity was found to Terrimonas lutea DYT (97.1%). The draft genome of strain NA20T had a total length of 7 144 125 base pairs. A total of 5659 genes were identified, of which 5613 were CDS and 46 RNA genes were assigned a putative function. Mining the genomes revealed the presence of 225 carbohydrate genes out of 1334 genes. Strain NA20T contained iso-C15 : 0, iso-C15 : 0 G, iso-C17 : 0 3-OH and summed feature 3 (C16 : 1 ω7c and/or C16 : 1 ω6c) as major fatty acids. The predominant quinone was MK-7. The major polar lipids were phosphatidylethanolamine, one unknown polar lipid and one unknown aminophospholipid. Additionally, the functional analysis of NA20T showed the conversion of protopanaxatriol-mix type major ginsenosides (Rb1, Rc and Rd) to minor ginsenosides F2 and weak conversion of Rh2 and C-K within 24 h. As a result, the genotypic, phenotypic and taxonomic analyses support the affiliation of NA20T within the genus Terrimonas, for which the name Terrimonas ginsenosidimutans sp. nov. is proposed. The type strain is NA20T (=KACC 22218T=LMG 32198T).

Ketonization of Ginsenoside C-K by Novel Recombinant 3-ß-Hydroxysteroid Dehydrogenases and Effect on Human Fibroblast Cells.

BACKGROUND AND OBJECTIVE: The ginsenoside compound K (C-K) (which is a de-glycosylated derivative of major ginsenosides) is effective in the treatment of cancer, diabetes, inflammation, allergy, angiogenesis, aging, and has neuroprotective, and hepatoprotective than other minor ginsenosides. Thus, a lot of studies have been focused on the conversion of major ginsenosides to minor ginsenosides using glycoside hydrolases but there is no study yet published for the bioconversion of minor ginsenosides into another high pharmacological active compound. Therefore, the objective of this study to identify a new gene (besides the glycoside hydrolases) for the conversion of minor ginsenosides C-K into another highly pharmacological active compound. METHODS AND RESULTS: Lactobacillus brevis which was isolated from Kimchi has showed the ginsenoside C-K altering capabilities. From this strain, a novel potent decarboxylation gene, named HSDLb1, was isolated and expressed in Escherichia coli BL21 (DE3) using the pMAL-c5X vector system. Recombinant HSDLb1 was also characterized. The HSDLb1 consists of 774 bp (258 amino acids residues) with a predicted molecular mass of 28.64 kDa. The optimum enzyme activity was recorded at pH 6.0-8.0 and temperature 30 °C. Recombinant HSDLb1 effectively transformed the ginsenoside C-K to 12-ß-hydroxydammar-3-one-20(S)-O-ß-D-glucopyranoside (3-oxo-C-K). The experimental data proved that recombinant HSDLb1 strongly ketonized the hydroxyl (-O-H) group at C-3 of C-K via the following pathway: C-K → 3-oxo-C-K. In vitro study, 3-oxo-C-K showed higher solubility than C-K, and no cytotoxicity to fibroblast cells. In addition, 3-oxo-C-K induced the inhibitory activity of ultraviolet A (UVA) against matrix metalloproteinase-1 (MMP-1) and promoted procollagen type I synthesis. Based on these expectations, we hypothesized that 3-oxo-C-K can be used in cosmetic products to block UV radiations and anti-ageing agent. Furthermore, we expect that 3-oxo-C-K will show higher efficacy than C-K for the treatment of cancer, ageing and other related diseases, for which more studies are needed.

Characterization of four novel bacterial species of the genus Sphingomonas, Sphingomonas anseongensis, Sphingomonas alba, Sphingomonas brevis and Sphingomonas hankyongi sp.nov., isolated from wet land.

Four novel bacterial strains, designated as RG327T, SE158T, RB56-2T and SE220T, were isolated from wet soil in the Republic of Korea. To determine their taxonomic positions, the strains were fully characterized. On the basis of genomic information (16S rRNA gene and draft genome sequences), all four isolates represent members of the genus Sphingomonas. The draft genomes of RG327T, SE158T, RB56-2T and SE220T consisted of circular chromosomes of 2 226 119, 2 507 338, 2 593 639 and 2 548 888 base pairs with DNA G+C contents of 64.6, 63.6, 63.0 and 63.1 %, respectively. All the isolates contained ubiquinone Q-10 as the predominant quinone compound and a fatty acid profile with C16 : 0, C17 : 1ω6c, C18 : 1 2-OH, summed feature 3 (C16 : 1ω7c/C16 : 1ω6c) and summed feature 8 (C18 : 1ω7c/C18 : 1ω6c) as the major fatty acids, supporting the affiliation of strains RG327T, SE158T, RB56-2T and SE220T to the genus Sphingomonas. The major identified polar lipids in all four novel isolates were phosphatidylglycerol, diphosphatidylglycerol, phosphatidylethanolamine, sphingoglycolipid and phosphatidylcholine. Moreover, the physiological, biochemical results and low level of DNA-DNA relatedness and average nucleotide identity values allowed the phenotypic and genotypic differentiation of RG327T, SE158T, RB56-2T and SE220T from other species of the genus Sphingomonas with validly published names and indicated that they represented novel species of the genus Sphingomonas, for which the names Sphingomonas anseongensis sp. nov. (RG327T = KACC 22409T = LMG 32497T), Sphingomonas alba sp. nov. (SE158T = KACC 224408T = LMG 324498T), Sphingomonas brevis (RB56-2T = KACC 22410T = LMG 32496T) and Sphingomonas hankyongi sp. nov., (SE220T = KACC 22406T = LMG 32499T) are proposed.

Repressing effect of transformed ginsenoside Rg3-mix against LPS-induced inflammation in RAW264.7 macrophage cells.

BACKGROUND: Rg3-ginsenoside, a protopanaxadiol saponin, is a well-known adaptogen used for the prevention of cancer and inflammation. However, despite its distinct biological activity, the concentration of Rg3 in the total ginseng extract is insufficient for therapeutic applications. This study aims to convert PPD-class of major ginsenosides into a mixture of minor ginsenoside, to analyze its immune-regulatory role in macrophage cells. RESULTS: Using heat and organic acid treatment, three major ginsenosides, Rc, Rd, and Rb1, were converted into a mixture of minor ginsenosides, GRg3-mix [Rg3(S), Rg3(R), Rg5, and Rk1]. Purity and content analysis of the transformed compound were performed using thin-layer chromatography (TLC) and high-performance liquid chromatography (HPLC), compared with their standards. Preceding with the anti-inflammatory activity of GRg3-mix, lipopolysaccharide (LPS)-stimulated murine RAW264.7 macrophage cells were treated with various concentrations of GRg3-mix (6.25, 12.5, 25, and 50 µg/mL). The cell viability assay revealed that the level of cell proliferation was increased, while the nitric oxide (NO) assay showed that NO production decreased dose-dependently in activated RAW264.7 cells. The obtained results were compared to those of pure Rg3(S) ≥ 98% (6.25, 12.5, and 25 µg/mL). Preliminary analysis of the CCK-8 and NO assay demonstrated that GRg3-mix can be used as an anti-inflammatory mediator, but mRNA and protein expression levels were evaluated for further confirmation. The doses of GRg3-mix significantly suppressed the initially upregulated mRNA and protein expression of inflammation-related enzymes and cytokines, namely inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), nuclear transcription factor kappa B (NF-κB), tumor necrosis factor (TNF-α), and interleukins (IL-6 and IL1B), as measured by reverse transcription-polymerase chain reaction and western blotting. CONCLUSIONS: Our pilot data confirmed that the mixture of minor ginsenosides, namely GRg3-mix, has high anti-inflammatory activity and has an easy production procedure.

Production of Prosaikogenin F, Prosaikogenin G, Saikogenin F and Saikogenin G by the Recombinant Enzymatic Hydrolysis of Saikosaponin and their Anti-Cancer Effect.

The saponins of Bupleurum falcatum L., saikosaponins, are the major components responsible for its pharmacological and biological activities. However, the anti-cancer effects of prosaikogenin and saikogenin, which are glycoside hydrolyzed saikosaponins, are still unknown due to its rarity in plants. In this study, we applied two recombinant glycoside hydrolases that exhibit glycoside cleavage activity with saikosaponins. The two enzymes, BglPm and BglLk, were cloned from Paenibacillus mucilaginosus and Lactobacillus koreensis, and exhibited good activity between 30-37 °C and pH 6.5-7.0. Saikosaponin A and D were purified and obtained from the crude B. falcatum L. extract using preparative high performance liquid chromatography technique. Saikosaponin A and D were converted into saikogenin F via prosaikogenin F, and saikogenin G via prosaikogenin G using enzyme transformation with high ß-glycosidase activity. The two saikogenin and two prosaikogenin compounds were purified using a silica column to obtain 78.1, 62.4, 8.3, and 7.5 mg of prosaikogenin F, prosaikogenin G, saikogenin F, and saikogenin G, respectively, each with 98% purity. The anti-cancer effect of the six highly purified saikosaponins was investigated in the human colon cancer cell line HCT 116. The results suggested that saikosaponins and prosaikogenins markedly inhibit the growth of the cancer cell line. Thus, this enzymatic technology could significantly improve the production of saponin metabolites of B. falcatum L.

Enhanced production of ginsenoside Rh2(S) from PPD-type major ginsenosides using BglSk cloned from Saccharibacillus kuerlensis together with two glycosidase in series.

BACKGROUND: Ginsenoside Rh2(S) is a promising compound for the prevention of various kinds of cancers, inflammation, and diabetes. However, due to its low concentration (<0.02%), researchers are still trying to find an efficient glycoside hydrolase for the scaled-up production of Rh2(S). METHOD: Three glycoside hydrolases (BglBX10, Abf22-3, and BglSk) were cloned in Escherichia coli BL21 (DE3) and the expressed recombinant enzyme was used for the scaled-up production of Rh2(S) through the conversion of PPD-type (protopanaxadiol) major ginsenosides (Rb1, Rc, and Rd, except Rb2) extracted from Korean red ginseng. Specific and specialized bioconversion pathways were designed that evolved the initial bioconversion of PPD-mix â†’ Rg3(S) â†’ Rh2(S). The reaction was started with 50 mg/mL of PPD-mix, 20 mg/mL of BglBX10, Abf22-3, and BglSk in series, respectively. The process was completed in a 10 L jar fermenter with a 5 L working volume at 37 °C for 48 hrs. RESULTS: The designed bioconversion pathways show that Abf22-3 and BglBX10 were responsible for the conversion of Rb1, Rc and Rd â†’ Rg3(S), and then Rg3(S) was completely transformed to Rh2(S) by BglSk. As a result, 15.1 g of ginsenoside Rh2(S) with 98.0 ± 0.2% purity was obtained after strict purification using the Prep-HPLC system with a 100 φ diameter column. Additionally, BglSk was also investigated for its production activity with seven different kinds of PPD-mix type ginsenosides. CONCLUSION: Our pilot data demonstrate that BglSk is a suitable enzyme for the gram unit production of ginsenoside Rh2(S) at the industrial level.

Phnomibacter ginsenosidimutans gen. nov., sp. nov., a novel glycoside hydrolase positive bacterial strain with ginsenoside hydrolysing activity.

The conversion of major ginsenosides into minor ginsenosides attracts a lot of interest because of their biological and pharmaceutical activities. Therefore, for the conversion of ginsenosides, finding a novel competent glycoside hydrolase-producing bacterial strain is useful for future research studies and the mass production of minor ginsenosides. Wastewater samples were collected and screened for novel glycoside hydrolase bacterial strains using Reasoner's 2A+aesculin agar medium. As a result, a novel glycoside hydrolase positive bacterial strain (SB-02T) was identified and subjected to a polyphasic taxonomic analysis. Based on genome analysis, strain SB-02T was found to be affiliated with the family Chitinophagaceae and have less than 92.8 % sequence similarity to other members of the same family. Functional analysis indicated that SB-02T was able to hydrolyse the ginsenosides Rb1, Rc and Rd to F2 and C-K. Due to the conversion of ginsenosides, the strain's genome was sequenced and the genes were annotated by the NCBI. The average amino acid identity and average nucleotide identity values between SB-02T and the available reference genomes were 65.7 and 65.9 %, respectively. The novel isolate contained MK-7 as the predominant menaquinone, the major polyamine putrescine, and iso-C15 : 0, iso-C15 : 1 G and iso-C17 : 0 3-OH as major fatty acids. The major polar lipids were diphosphatidylglycerol, phosphatidylglycerol and phosphatidylethanolamine. Thus, based on the data presented here, strain SB-02T represents a novel species within a new genus in the family Chitinophagaceae, for which the name Phnomibacter ginsenosidimutans gen. nov., sp. nov. is proposed. The type strain of Phnomibacter ginsenosidimutans is SB-02T (=KACC 21266T=LMG 31707T). The genome annotation of SB-02T shows many glycoside hydrolase genes, which may be responsible for the efficient production of many kinds of minor ginsenosides and will be very helpful for future research (target gene cloning) and mass production of either F2 or C-K.

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 BR5-29T), was isolated and its taxonomy was studied. Phylogenetic study based on the 16S rRNA and draft genome sequence placed the strain BR5-29T 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 BR5-29T 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 BR5-29T showed 225 carbohydrate genes which may be responsible for the conversion of major ginsenosides to minor ginsenosides. Strain BR5-29T contained MK-7 as a predominant quinone, and iso-C15:0, iso-C15:0 G, iso-C17:0 3-OH, and C16:1 ω7c and/or C16:1 ω6c (summed feature 3) as major fatty acids. The polar lipids found in the strain BR5-29T 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 C12:0, iso-C17:0 2-OH and iso-C15:1 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 BR5-29T 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 BR5-29T (= KACC 19446T = LMG 30462T). 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-4T) isolated from granules of a wastewater treatment plant, was characterized by a polyphasic approach to clarify its taxonomic position. Strain Gr-4T 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-4T belongs to the genus Luteimonas of the family Xanthomonadaceae and was most closely related to Luteimonas padinae CDR SL 15T (99.1%), Luteimonas terricola DSM 22344T (98.5%) and Luteimonas arsenica 26-35T (97.6). The genome comprises 2,917,404 bp with a G+C content of 70.5 mol%. The ANI value between strain Gr-4T and Luteimonas padinae CDR SL 15T was 87.3%. The DNA-DNA relatedness value between strain Gr-4T and Luteimonas padinae CDR SL 15T, Luteimonas terricola DSM 22344T was 36.4 ± 1.3% and 14.2 ± 1.7%, respectively. The predominant quinone was Q-8. The major fatty acids were iso-C15:0, iso-C16:0 and summed feature 9 (comprising iso-C17:1ω9c and/or C16:0 10-methyl) supported the affiliation of strain Gr-4T 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-4T 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-4T (=KACC 16614T = JCM 18203T).

Devosia ginsengisoli sp. nov., isolated from ginseng cultivation soil.

A Gram-stain-negative, strictly aerobic, motile, ivory-coloured and rod-shaped bacterium (designated Gsoil 520T) isolated from ginseng cultivation soil was characterized by using a polyphasic approach to clarify its taxonomic position. Strain Gsoil 520T was observed to grow optimally at 30 °C and pH 7.0 on Reasoner's 2A agar medium. The results of phylogenetic analysis, based on 16S rRNA gene sequence similarities, indicated that Gsoil 520T belongs to the genus Devosia of the family Hyphomicrobiaceae and was most closely related to Devosia epidermidihirudinis E84T (98.0 %), Devosia yakushimensis Yak96BT (97.7 %), Devosia neptuniae J1T (97.7 %) and Devosia chinhatensis IPL18T (96.8 %). The complete genome of strain Gsoil 520T is a presumptive circular chromosome of 4 480 314 base pairs having G+C content of 63.7 mol%. A total of 4 354 genes, 4 303 CDS and 43 rRNA genes were assigned a putative function. The major isoprenoid quinone was Q-10. The main polar lipids were phosphatidylglycerol, diphosphatidylglycerol and two unidentified aminolipids (AL1 and AL3). The predominant fatty acids of strain Gsoil 520T were C18 : 1ω7c 11-methyl, C16 : 0 and C18 : 1ω7c/C18 : 1ω6c (summed feature 8) supporting the affiliation of strain Gsoil 520T to the genus Devosia. The low values of DNA-DNA hybridization distinguished strain Gsoil 520T from the recognized species of the genus Devosia. Thus, the novel isolate represents a novel species of the genus Devosia, for which the name Devosia ginsengisoli sp. nov. is proposed, with the type strain Gsoil 520T (=KACC 19440T=LMG 30329T).

Lysobacter lacus sp. nov., isolated from from lake sediment.

An aerobic and Gram-stain-negative bacterial strain, designated UKS-15T, was isolated from lake water in the Republic of Korea. Results of 16S rRNA gene sequence and phylogenetic analyses indicated that the novel isolate belongs to the genus Lysobacter and was most closely related to Lysobacter xinjiangensis RCML-52T (98.0 %), Lysobacter mobilis 9 NM-14T (97.4 %) and Lysobacter humi FJY8T (97.2 %). The DNA G+C content was 69.1 mol%. Strain UKS-15T possessed ubiquinone-8 (Q-8) as the sole respiratory quinone and the fatty acid profile comprised iso-C15 : 0, iso-C17 : 0 and summed feature 9 (iso-C17 : 1 ω9c and/or C16 : 0 10-methyl) as its major components. The major polar lipids were phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol and one unidentified aminophospholipid. Moreover, the physiological and biochemical results and low level of DNA-DNA relatedness (<22.0 %) allowed the phenotypic and genotypic differentiation of strain UKS-15T from other Lysobacter species. Therefore, on the basis of the data from this polyphasic taxonomic study, strain UKS-15T should represent a novel species of the genus Lysobacter, for which the name Lysobacter lacus sp. nov. is proposed. The type strain is UKS-15T (=JCM 30983T=KACC 18719T).

Exploration and Characterization of Novel Glycoside Hydrolases from the Whole Genome of Lactobacillus ginsenosidimutans and Enriched Production of Minor Ginsenoside Rg3(S) by a Recombinant Enzymatic Process.

BACKGROUND: Several studies have reported that ginsenoside Rg3(S) is effective in treating metastatic diseases, obesity, and various cancers, however, its presence in white ginseng cannot be estimated, and only a limited amount is present in red ginseng. Therefore, the use of recombinant glycosidases from a Generally Recognized As Safe (GRAS) host strain is a promising approach to enhance production of Rg3(S), which may improve nutritional activity, human health, and quality of life. METHOD: Lactobacillus ginsenosidimutans EMML 3041T, which was isolated from Korean fermented pickle (kimchi), presents ginsenoside-converting abilities. The strain was used to enrich the production of Rg3(S) by fermenting protopanaxadiol (PPD)-mix-type major ginsenosides (Rb1, Rb2, Rc, and Rd) in four different types of food-grade media (1, MRS; 2, Basel Food-Grade medium; 3, Basel Food-Grade medium-I, and 4, Basel Food-Grade medium-II). Due to its tendency to produce Rg3(S), the presence of glycoside hydrolase in Lactobacillus ginsenosidimutans was proposed, the whole genome was sequenced, and the probable glycoside hydrolase gene for ginsenoside conversion was cloned. RESULTS: The L. ginsenosidimutans EMML 3041T strain was whole genome sequenced to identify the target genes. After genome sequencing, 12 sets of glycoside hydrolases were identified, of which seven sets (α,ß-glucosidase and α,ß-galactosidase) were cloned in Escherichia coli BL21 (DE3) using the pGEX4T-1 vector system. Among the sets of clones, only one clone (BglL.gin-952) showed ginsenoside-transforming abilities. The recombinant BglL.gin-952 comprised 952 amino acid residues and belonged to glycoside hydrolase family 3. The enzyme exhibited optimal activity at 55 °C and a pH of 7.5 and showed a promising conversion ability of major ginsenoside Rb1→Rd→Rg3(S). The recombinant enzyme (GST-BglL.gin-952) was used to mass produce Rg3(S) from major ginsenoside Rb1. Scale-up of production using 50 g of Rb1 resulted in 30 g of Rg3(S) with 74.3% chromatography purity. CONCLUSION: Our preliminary data demonstrated that this enzyme would be beneficial in the preparation of pharmacologically active minor ginsenoside Rg3(S) in the functional food and pharmaceutical industries.

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

In this study, a novel ginsenoside transforming bacterium, strain W1-2-3T, was isolated from mineral water. The 16S rRNA gene sequence analysis showed that strain W1-2-3T shares 93.7-92.2% sequence similarity with the members of the family Sphingomonadaceae and makes a group with Sphingoaurantiacus capsulatus YLT33T (93.7%) and S. polygranulatus MC 3718T (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 W1-2-3T was found to contain ubiquinone-10 as the predominant quinone and the fatty acids C16:1, C17:1ω6c, C14:0 2-OH, summed feature 3 (C16:1ω6c/C16:1ω7c) and summed feature 8 (C18:1ω6c/C18:1ω7c). The DNA G+C content was determined to be 65.9 mol%. Strain W1-2-3T 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 W1-2-3T 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 W1-2-3T 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 W1-2-3T (= KACC 18307T = LMG 28594T).

Simplicispira hankyongi sp. nov., a novel denitrifying bacterium isolated from sludge.

A Gram-stain-negative, facultatively anaerobic, motile, light-yellow, and rod-shaped bacterium, designated as NY-02T, was isolated from the sludge of a wastewater treatment plant in Hanam City, Republic of Korea. The comparison of 16S rRNA gene sequences revealed that the strain formed a distinct lineage within the genus Simplicispira and was most closely related to S. suum SC1-8T (99.0%), S. limi EMB325T (98.3%), S. psychrophila LMG 5408T (98.2%), and S. piscis RSG39T (97.4%). Both average nucleotide identity (ANI) and DNA-DNA hybridization (DDH) values between strain NY-02T, and its closes type strains [S. suum SC1-8T, S. limi EMB325T, S. psychrophila LMG 5408T, and S. piscis RSG39T] were lower than the cut-off (≥ 95-96% for ANI and ≥ 70% for DDH) to define a bacterial species. The genome comprises of 3,709,074 bp with a G + C content of 64.2 mol%. Ubiquinone 8 (Q-8) was the predominant quinone. The major fatty acids were C16:0 and summed feature 3 (C16:1ω7c and/or C16:1ω6c), and the major polar lipids were phosphatidylglycerol, diphosphatidylglycerol, and phosphatidylethanolamine. The results of the physiological, biochemical, and taxonomic analyses in addition to low ANI and DNA-DNA relatedness values (82.2% and < 34.0%, respectively) indicate that the strain NY-02T represents a novel species of the genus Simplicispira. The name proposed for strain NY-02T (= KACC 19731T = LMG 31165T) is Simplicispira hankyongi sp. nov.

Mesorhizobium denitrificans sp. nov., a novel denitrifying bacterium isolated from sludge.

A Gram-stain-negative, non-spore-forming, facultative, rod-shaped bacterium (designated LA-28T) was isolated from a sludge sample from a wastewater treatment plant in Hanam city, Republic of Korea. On the basis of 16S rRNA gene sequencing, strain LA-28T clustered with species of the genus Mesorhizobium and appeared closely related to M. jarvisii LMG 28313T (96.8%), M. waimense ICMP 19557T (96.7%), and M. huakuii LMG 14107T (96.7%). Growth occurs at 18-40°C on R2A medium in the presence of 1-4% NaCl (w/v) and at pH 6-8. The DNA G+C content was 61.2 mol%, and the predominant quinone was ubiquinone-10 (Q-10). The major cellular fatty acids (> 5%) were C16:0, C19:0ω8c cyclo, C18:1ω7c 11-methyl, and C18:1ω7c and/or C18:1ω6c (summed feature 8). Major polar lipids were phosphatidylglycerol (PG), phosphatidylethanolamine (PE), phosphatidyl-N-methylethanolamine (PME), and phosphatidylcholine (PC). Physiological and biochemical characteristics indicated that strain LA-28T represents a novel species of the genus Mesorhizobium, for which the name Mesorhizobium denitrificans sp. nov. is proposed. The type strain is LA-28T (= KACC 19675T = LMG 30806T).

Caballeronia ginsengisoli sp. nov., isolated from ginseng cultivating soil.

A Gram-stain-negative, strictly aerobic, non-motile, ivory colored and rod-shaped bacterium (designated Gsoil 652T) isolated from ginseng cultivating soil, was characterized using a polyphasic approach to clarify its taxonomic position. Strain Gsoil 652T was observed to grow optimally at 30 °C and at pH 7.0 on R2A agar medium. Phylogenetic analysis, based on 16S rRNA gene sequences similarities, indicated that Gsoil 652T belongs to the genus Caballeronia of the family Burkholderiaceae and was most closely related to Caballeronia choica LMG 22940T (98.9%), Caballeronia udeis LMG 27134T (98.9%), Caballeronia sordidicola LMG 22029T (98.2%) and Caballeronia humi LMG 22934T (98.1%). The DNA G+C content was 62.1 mol% and Q-8 was the major isoprenoid quinone. The main polar lipids were diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, unidentified aminophospholipid, and unidentified phospholipid. The predominant fatty acids were C16:0, C17:0 cyclo and C19:0 cyclo ω8c. The DNA-DNA relatedness value between strain Gsoil 652T and closely related type strains of Caballeronia species were less than 36.0%. Moreover, strain Gsoil 652T could be distinguished phenotypically from the recognized species of the genus Caballeronia. The novel isolate, therefore, represents a novel species, for which the name Caballeronia ginsengisoli sp. nov. is proposed, with the type strain Gsoil 652T (= KACC 19441T = LMG 30326T).

Anti-Inflammatory Effect of Ginsenoside Rh2-Mix on Lipopolysaccharide-Stimulated RAW 264.7 Murine Macrophage Cells.

Ginsenoside Rh2, a protopanaxadiol saponin from ginseng, has been reported to have strong anti-inflammatory activity. However, the concentration of ginsenoside Rh2 is very low (>0.001%) in the total ginseng extracted, which is not enough for production despite its high pharmacological effects. Thus, in this study, we evaluated the anti-inflammatory effect of ginsenoside Rh2-mix (GRh2-mix) on lipopolysaccharide (LPS)-stimulated RAW 264.7 murine macrophage cells. From the high-performance liquid chromatography analysis, it was confirmed that the GRh2-mix was mainly composed of 20(S)-Rh2, 20(R)-Rh2, Rk2, and Rh3. The LPS-stimulated RAW 264.7 cells were treated with different concentrations of GRh2-mix (100, 200, 400, 500 µg/mL). The cell counting kit-8 assay showed that the GRh2-mix treatment increased cell proliferation in LPS-stimulated RAW 264.7 murine macrophage cells. The GRh2-mix inhibited nitric oxide production in a dose-dependent manner, suggesting an anti-inflammatory effect. Furthermore, reverse transcription polymerase chain reaction and Western blot results also indicated that the GRh2-mix suppressed inflammatory genes such as iNOS, TNF-α, COX-2, IL-1ß, IL-6, and NF-κB. In summary, these results suggest that the GRh2-mix exhibits anti-inflammatory activity via the downregulation of the NF-κB pathway and has high efficiency with a simple production procedure.

Brevibacterium hankyongi sp. nov., isolated from compost.

A Gram-positive, strictly aerobic, non-motile, milky-white to creamy coloured and rod-shaped bacterium, designated BS05T, was isolated from compost. Phylogenetic analysis based on 16S rRNA gene sequence comparison revealed that the strain formed a distinct lineage within the genus Brevibacterium and was most closely related to Brevibacterium avium NCFB 3055T (96.3 %), Brevibacterium oceani BBH7T (96.2 %) and Brevibacterium epidermidis NBRC 14811T (96.1 %). The DNA G+C content was 62.3 mol%. The predominant quinone was MK-8(H2). The major fatty acids were anteiso-C15 : 0, anteiso-C17 : 0, iso-C16 : 0 and iso-C15 : 0. The cell-wall peptidoglycan of strain BS05T contained meso-diaminopimelic acid. The major polar lipid was phosphatidylglycerol. Moreover, the low sequence similarity of the 16S rRNA gene sequencing, physiological, biochemical and chemotaxonomic analyses allowed the phenotypic and genotypic differentiation of strain BS05T from the recognized species of the genus Brevibacterium. Therefore, strain BS05T represents a novel species of the genus Brevibacterium, for which the name Brevibacteriumhankyongi sp. nov. is proposed, with the type strain BS05T (=KACC 18875T=LMG 29562T).

Brevibacterium anseongense sp. nov., isolated from soil of ginseng field.

Gram-positive, aerobic, non-motile, pale-yellow, and rodshaped bacterium, designated as Gsoil 188T, was isolated from the soil of a ginseng field in Pocheon, South Korea. A phylogenetic analysis based on 16S rRNA gene sequence comparison revealed that the strain formed a distinct lineage within the genus Brevibacterium and was most closely related to B. epidermidis NBRC 14811T (98.4%), B. sediminis FXJ8.269T (98.2%), B. avium NCFB 3055T (98.1%), and B. oceani BBH7T (98.1%), while it shared less than 98.1% identity with the other species of this genus. The DNA G + C content was 68.1 mol%. The predominant quinone was MK-8(H2). The major fatty acids were anteiso-C15:0 and anteiso-C17:0. The cell wall peptidoglycan of strain Gsoil 188T contained meso-diaminopimelic acid. The major polar lipids were phosphatidylglycerol, diphosphatidylglycerol, and an unidentified aminolipid. The physiological and biochemical characteristics, low DNA-DNA relatedness values, and taxonomic analysis allowed the differentiation of strain Gsoil 188T from the other recognized species of the genus Brevibacterium. Therefore, strain Gsoil 188T represents a novel species of the genus Brevibacterium, for which the name Brevibacterium anseongense sp. nov. is proposed, with the type strain Gsoil 188T (= KACC 19439T = LMG 30331T).

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 BS18T, was isolated from compost and subjected to a polyphasic taxonomic analysis. On the basis of the results of 16S rRNA gene sequence analysis, BS18T represents a member of the genus Olivibacter of the family Sphingobacteriaceaeand is most closely related to Olivibacter oleidegradansTBF2/20.2T (93.7 %), Olivibacter jilunii 14-2AT (93.6 %), Olivibacter ginsengisoli Gsoil 060T (93.6 %), Pseudosphingobacterium domesticumDC186T (93.0 %) and shared ≤93.1 % sequence similarity with the other members of the genus Olivibacter. BS18T 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. BS18T 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, BS18T represents a novel species within the genus, for which the name Olivibacter ginsenosidimutans sp. nov. is proposed. The type strain of Olivibacter ginsenosidimutans is BS18T (=KACC 16612T=JCM 18200T). It is also proposed to transfer Pseudosphingobacterium domesticumto the genus Olivibacter, as Olivibacter domesticus comb. nov. (type strain DC186T=CCUG 54353T=LMG 23837T).