179 results on '"Kyoung-Su Kim"'
Search Results
52. A New Record and Characterization of Asparagus Purple Spot Caused by
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Joon-Hee, Han, Jong-Hwan, Shin, Teng, Fu, and Kyoung Su, Kim
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Stemphylium vesicarium ,cytochrome b ,Asparagus ,food and beverages ,purple spot ,Research Notes - Abstract
In 2017, small, elliptical, brownish purple spots on spears and ferns of asparagus were found in fields of Gangwon-do. The isolated fungal species was identified as an ascomycete Stemphylium vesicarium based on morphological characteristics and molecular phylogenic analyses including nucleotide sequences of the internal transcribed spacer (ITS), glyceraldehyde-3-phosphate dehydrogenase (GAPDH), and cytochrome b (cytb). A pathogenicity test revealed that S. vesicarium was the causal agent of purple spot disease on asparagus. The occurrence of purple spots caused by S. vesicarium on asparagus is the first report in Korea.
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- 2018
53. Distinct roles of the YPEL gene family in development and pathogenicity in the ascomycete fungus Magnaporthe oryzae
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Jong-Hwan Shin, Yong-Hwan Lee, Joon-Hee Han, and Kyoung Su Kim
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0106 biological sciences ,0301 basic medicine ,Virulence Factors ,Mutant ,lcsh:Medicine ,Conidiation ,Biology ,01 natural sciences ,Fungal Proteins ,03 medical and health sciences ,Homologous chromosome ,Gene family ,lcsh:Science ,Gene ,Pathogen ,Plant Diseases ,Cell Nucleus ,Genetics ,Appressorium ,Multidisciplinary ,lcsh:R ,fungi ,Nuclear Proteins ,Oryza ,Subcellular localization ,Magnaporthe ,030104 developmental biology ,lcsh:Q ,Gene Deletion ,010606 plant biology & botany - Abstract
Members of the Yippee-like (YPEL) gene family are highly conserved in eukaryotes and are homologous to the Drosophila yippee gene. In this study, we functionally characterized two YPEL-homologous genes, MoYPEL1 and MoYPEL2, in the rice blast pathogen Magnaporthe oryzae using the deletion mutants ΔMoypel1, ΔMoypel2, and ΔΔMoypel1,2. The MoYPEL1 deletion mutant was significantly defective in conidiation and unable to undergo appressorium development; however, deletion of MoYPEL2 resulted in a significant increase in conidiation and the abnormal development of two appressoria per conidium. These data demonstrate the opposite roles of each member of the YPEL gene family during the development of M. oryzae. The double mutant was phenotypically similar to the ΔMoypel1 mutant in conidiation, but similar to the ΔMoypel2 mutant in appressorium development. Subcellular localization of the MoYPEL1 protein was dynamic during appressorium development, while the MoYPEL2 protein consistently localized within the nuclei during developmental stages. Our studies indicate that the two YPEL gene family members play distinct roles in the developmental stages of M. oryzae, furthering our understanding of disease dissemination and development in fungi.
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- 2018
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54. A Small GTPase RHO2 Plays an Important Role in Pre-infection Development in the Rice Blast Pathogen
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Teng, Fu, Joon-Oh, Kim, Joon-Hee, Han, Adiyantara, Gumilang, Yong-Hwan, Lee, and Kyoung Su, Kim
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fungi ,Rho GTPase ,food and beverages ,pathogenicity ,Magnaporthe oryzae ,Research Article ,appressorium formation - Abstract
The rice blast pathogen Magnaporthe oryzae is a global threat to rice production. Here we characterized RHO2 gene (MGG_02457) that belongs to the Rho GTPase family, using a deletion mutant. This mutant ΔMorho2 exhibited no defects in conidiation and germination but developed only 6% of appressoria in response to a hydrophobic surface when compared to the wild-type progenitor. This result indicates that MoRHO2 plays a role in appressorium development. Furthermore, exogenous cAMP treatment on the mutant led to appressoria that exhibited abnormal morphology on both hydrophobic and hydrophilic surfaces. These outcomes suggested the involvement of MoRHO2 in cAMP-mediated appressorium development. ΔMorho2 mutation also delayed the development of appressorium-like structures (ALS) at hyphal tips on hydrophobic surface, which were also abnormally shaped. These results suggested that MoRHO2 is involved in morphological development of appressoria and ALS from conidia and hyphae, respectively. As expected, ΔMorho2 mutant was defective in plant penetration, but was still able to cause lesions, albeit at a reduced rate on wounded plants. These results implied that MoRHO2 plays a role in M. oryzae virulence as well.
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- 2018
55. Biological Control of Fusarium Stalk Rot of Maize Using Bacillus spp
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Joon-Oh Kim, Gi-Chang Park, Kyoung Su Kim, and Joon-Hee Han
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Fusarium ,biology ,Biological pest control ,Fusarium spp ,Plant Science ,Bacillus sp ,biology.organism_classification ,lcsh:S1-972 ,Biochemistry ,Maize ,Horticulture ,Stalk ,Biological control ,Bacillus spp ,lcsh:Agriculture (General) ,Agronomy and Crop Science ,Molecular Biology ,Biotechnology - Abstract
Maize (Zea mays L.) is an economically important crop in worldwide. While the consumption of the maize is steadily increasing, the yield is decreasing due to continuous mono-cultivation and infection of soil-borne fungal pathogens such as Fusarium species. Recently, stalk rot disease in maize, caused by F. subglutinans and F. temperatum has been reported in Korea. In this study, we isolated bacterial isolates in rhizosphere soil of maize and subsequently tested for antagonistic activities against F. subglutinans and F. temperatum. A total of 1,357 bacterial strains were isolated from rhizosphere. Among them three bacterial isolates (GC02, GC07, GC08) were selected, based on antagonistic effects against Fusarium species. The isolates GC02 and GC07 were most efficient in inhibiting the mycelium growth of the pathogens. The three isolates GC02, GC07 and GC08 were identified as Bacillus methylotrophicus, B. amyloliquefaciens and B. thuringiensis using 16S rRNA sequence analysis, respectively. GC02 and GC07 bacterial suspensions were able to suppress over 80% conidial germination of the pathogens. GC02, GC07 and GC08 were capable of producing large quantities of protease enzymes, whereas the isolates GC07 and GC08 produced cellulase enzymes. The isolates GC02 and GC07 were more efficient in phosphate solubilization and siderophore production than GC08. Analysis of disease suppression revealed that GC07 was most effective in suppressing the disease development of stalk rot. It was also found that B. methylotrophicus GC02 and B. amyloliquefaciens GC07 have an ability to inhibit the growth of other plant pathogenic fungi. This study indicated B. methylotrophicus GC02 and B. amyloliquefaciens GC07 has potential for being used for the development of a biological control agent.
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- 2015
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56. A fraction from Dojuksan 30% ethanol extract exerts its anti-inflammatory effects through Nrf2-dependent heme oxygenase-1 expression
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Hyuncheol Oh, Wonmin Ko, Sung-Joo Park, Jun-Hyeog Jang, Dong-Sung Lee, Gi-Sang Bae, Kyoung Su Kim, and Youn-Chul Kim
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Lipopolysaccharides ,0301 basic medicine ,medicine.drug_class ,Interleukin-1beta ,Nitric Oxide Synthase Type II ,Pharmacology ,Nitric Oxide ,Dinoprostone ,Anti-inflammatory ,Cell Line ,Nitric oxide ,Mice ,03 medical and health sciences ,chemistry.chemical_compound ,Genetics ,medicine ,Animals ,Humans ,Prostaglandin E2 ,Heme ,Inflammation ,biology ,Nuclear Respiratory Factor 1 ,business.industry ,NF-kappa B ,Biological activity ,General Medicine ,Nitric oxide synthase ,Heme oxygenase ,030104 developmental biology ,Gene Expression Regulation ,chemistry ,Cyclooxygenase 2 ,Apoptosis ,Immunology ,biology.protein ,business ,Heme Oxygenase-1 ,Drugs, Chinese Herbal ,medicine.drug - Abstract
Dojuksan is a traditional herbal medicine used in Korea and China to treat urinary diseases. In the present study, we aimed to examine the anti-inflammatory effects of an ethanol solvent extract of Dojuksan and a fraction (by bioassay-guided fractionation) derived from this extract, and to elucidate the specific mechanisms involved. The Dojuksan 30% ethanol extract (DEE) had a more significant and potent anti-inflammatory effect than the Dojuksan water extract (DWE). DEE markedly inhibited the production of inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), nitric oxide (NO), prostaglandin E2 (PGE2), tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β), as well as nuclear factor-κB (NF-κB) binding activity. We found that the anti-inflammatory effects of DEE were mediated by the induction of nuclear factor E2-related factor 2 (Nrf2)-dependent heme oxygenase-1 (HO-1). To further explore the anti-inflammatory effects of DEE, we generated 6 different fractions of DEE. Of these, DEE-5 decreased the production of NO more significantly than the other fractions. DEE-5 also significantly decreased the expression of iNOS and COX-2, and the production of NO, PGE2, TNF-α and IL-1β. In addition, DEE-5 also significantly increased HO-1 levels; HO-1 significanlty contributed to the inhibitory effects of DEE-5 on the production of pro-inflammatory mediators. In this study, we determined whether the choice of extraction solvent affects the biological activity of Dojuksan, a traditional herbal formula. Our findings demonstrate that DEE and a fraction derived from this extract exerts anti-inflammatory effects through Nrf2‑dependent HO-1 expression, and that DEE may thus have greater potential therapeutic application than DWE.
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- 2015
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57. Role of theMoYAK1protein kinase gene inMagnaporthe oryzaedevelopment and pathogenicity
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Jong-Hwan Shin, Kyoung Su Kim, Yong-Hwan Lee, Joon-Hee Han, and Hye-Min Lee
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Fungal protein ,Appressorium ,Magnaporthe ,Kinase ,Saccharomyces cerevisiae ,Mutant ,food and beverages ,Conidiation ,Biology ,biology.organism_classification ,Microbiology ,Protein kinase A ,Ecology, Evolution, Behavior and Systematics - Abstract
Conidiation and appressorium differentiation are key processes for polycyclic dissemination and infection in many pathogens. Our previous study using DNA microarray led to the discovery of the MoYAK1 gene in Magnaporthe oryzae that is orthologous to YAK1 in Saccharomyces cerevisiae. Although the mechanistic roles of YAK1 in S. cerevisiae have been described, roles of MoYAK1 in M. oryzae, a phytopathogenic fungus responsible for rice blast, remain uncharacterized. Targeted disruption of MoYAK1 results in pleiotropic defects in M. oryzae development and pathogenicity. The ΔMoyak1 mutant exhibits a severe reduction in aerial hyphal formation and conidiation. Conidia in the ΔMoyak1 are delayed in germination and demonstrate decreased glycogen content in a conidial age-dependent manner. The expression of hydrophobin-coding genes is dramatically changed in the ΔMoyak1 mutant, leading to a loss of surface hydrophobicity. Unlike the complete inability of the ΔMoyak1 mutant to develop appressoria on an inductive surface, the mutant forms appressoria of abnormal morphology in response to exogenous cyclic adenosine-5'-monophosphate and host-driven signals, which are all defective in penetrating host tissues due to abnormalities in glycogen and lipid metabolism, turgor generation and cell wall integrity. These data indicate that MoYAK1 is a protein kinase important for the development and pathogenicity of M. oryzae.
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- 2015
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58. Effects of Relative Humidity and Air Injection on Physiological and Stomatal Responses in Phalaenopsis during Acclimatization
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Jae Kyung Kim, Yeo Joog Yoon, Kyoung Su Kim, Kiyoung Choi, and Jong-Kuk Na
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0106 biological sciences ,0301 basic medicine ,Chlorophyll content ,Horticulture ,Biology ,biology.organism_classification ,01 natural sciences ,Acclimatization ,03 medical and health sciences ,030104 developmental biology ,Relative humidity ,Phalaenopsis ,Secondary air injection ,010606 plant biology & botany - Published
- 2018
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59. Subsea Equipment Decommissioning Using Fiber Rope
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Do Kyun Kim, Kyoung-Su Kim, Han-Suk Choi, Seungman Kim, and Eun-Jee Cheon
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Offset (computer science) ,Payload ,lcsh:TA1-2040 ,Fiber (computer science) ,Line (geometry) ,lcsh:Engineering (General). Civil engineering (General) ,Nuclear decommissioning ,Critical length ,Marine engineering ,Rope ,Subsea - Abstract
A comparative study of lifting lines for subsea equipment decommissioning was conducted to evaluate the applicability of fiber ropes. Generally, conventional steel wire ropes are used for subsea equipment decommissioning operations, but there are some disadvantages in using steel wires as the lifting lines at deepwater depth. To overcome the disadvantages, fiber ropes are proposed for using as lifting lines. The comparative methods to evaluate the performance of both lifting lines include three sections of calculations, payload capacity, and horizontal offset due to current, critical length of lifting line. Moreover, dynamic analysis using Orcaflex was performed to compare the dynamic forces occurring in the lifting lines during subsea equipment decommissioning. The results showed that the fiber ropes had advantages in payload capacity, critical length of lifting line and lower dynamic forces occurred compared to the steel wire ropes at deepwater depth.
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- 2018
60. Characterization of the Maize Stalk Rot Pathogens Fusarium subglutinans and F. temperatum and the Effect of Fungicides on Their Mycelial Growth and Colony Formation
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Joon-Hee Han, Jong-Hwan Shin, Ju Kyong Lee, and Kyoung Su Kim
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QoI fungicides ,Fusarium stalk rot ,Articles ,lcsh:Plant culture ,Biology ,maize ,biology.organism_classification ,Fungicide ,Crop ,Fusarium subglutinans ,chemistry.chemical_compound ,Horticulture ,chemistry ,Stalk ,Agronomy ,Azoxystrobin ,DMI fungicides ,lcsh:SB1-1110 ,corn disease ,Agronomy and Crop Science ,Mycelium ,EC50 ,Tebuconazole - Abstract
Maize is a socioeconomically important crop in many countries. Recently, a high incidence of stalk rot disease has been reported in several maize fields in Gangwon province. In this report, we show that maize stalk rot is associated with the fungal pathogens Fusarium subglutinans and F. temperatum. Since no fungicides are available to control these pathogens on maize plants, we selected six fungicides (tebuconazole, difenoconazole, fluquinconazole, azoxystrobin, prochloraz and kresoxim-methyl) and examined their effectiveness against the two pathogens. The in vitro antifungal effects of the six fungicides on mycelial growth and colony formation were investigated. Based on the inhibition of mycelial growth, the most toxic fungicide was tebuconazole with 50% effective concentrations (EC50) of 3,000 μg/ml for both pathogens. Based on the inhibition of colony formation by the two pathogens, kresoxim-methyl was the most toxic fungicide with complete inhibition of colony formation at concentrations of 0.1 and 0.01 μg/ml for F. subglutinans and F. temperatum, respectively, whereas azoxystrobin was the least toxic fungicide with complete inhibition of colony formation at concentrations >3,000 μg/ml for both pathogens.
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- 2014
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61. Genome-wide analyses of DNA-binding proteins harboring AT-hook motifs and their functional roles in the rice blast pathogen, Magnaporthe oryzae
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Joon-Hee Han, Jong-Hwan Shin, and Kyoung Su Kim
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Genetics ,fungi ,Mutant ,food and beverages ,Virulence ,Conidiation ,Biology ,Biochemistry ,DNA-binding protein ,Chromatin ,High-mobility group ,Gene expression ,Molecular Biology ,Gene - Abstract
Transcriptional regulation is a complex process mediated by coordinated assembly complexes to ensure temporal and spatial gene expression. The AT-hook is a DNA-binding motif originally described in the high mobility group A of non-histone chromatin components. The AT-hook proteins bind to the minor groove of adenine–thymine (AT) rich regions of DNA and act as transcriptional cofactors coordinating nucleoproteins during transcriptional regulation. In this study, a genome-wide in silico analysis of AT-hook proteins was performed on the ascomycete plant pathogenic fungus, Magnaporthe oryzae. Quantitative real-time RT-PCR analysis revealed differential expression patterns of MoATH genes during development and plant infection. To increase our understanding of the functional role of AT-hook proteins in M. oryzae development and pathogenicity, a deletion mutant of MoATH10 was functionally characterized. Targeted deletion of MoATH10 significantly increased pigmentation and conidiation, indicating that MoATH10 is negatively involved in the regulation of pigmentation and conidiation in M. oryzae. Pathogenicity assays revealed that the ΔMoath10 mutant was less virulent. The reduced disease development of the ΔMoath10 mutant was due to a partial defect in invasive growth inside plant cells, but not appressorium-mediated penetration. These results suggest that MoATH10 is important for growth, development, and virulence in M. oryzae.
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- 2014
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62. The Cytoprotective Effect of Sulfuretin against tert-Butyl Hydroperoxide-Induced Hepatotoxicity through Nrf2/ARE and JNK/ERK MAPK-Mediated Heme Oxygenase-1 Expression
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Dong-Sung Lee, Youn-Chul Kim, Hyuncheol Oh, Kyoung Su Kim, Jun-Hyeog Jang, Wonmin Ko, Bin Li, and Gil-Saeng Jeong
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MAPK/ERK pathway ,sulfuretin ,Antioxidant ,medicine.medical_treatment ,hepatoprotective ,Pharmacology ,medicine.disease_cause ,lcsh:Chemistry ,tert-Butylhydroperoxide ,oxidative stress ,Phosphorylation ,lcsh:QH301-705.5 ,HepG2 cells ,Spectroscopy ,Anthracenes ,Mitogen-Activated Protein Kinase 1 ,chemistry.chemical_classification ,Mitogen-Activated Protein Kinase 3 ,Kinase ,Rhus verniciflua Stokes ,tert-butyl hydroperoxide ,heme oxygenase-1 ,Hep G2 Cells ,General Medicine ,Up-Regulation ,Computer Science Applications ,Cell biology ,Mitogen-Activated Protein Kinases ,Signal Transduction ,Cell Survival ,NF-E2-Related Factor 2 ,Protective Agents ,Article ,Catalysis ,Inorganic Chemistry ,medicine ,Humans ,Physical and Theoretical Chemistry ,Protein kinase A ,Molecular Biology ,Benzofurans ,Flavonoids ,Reactive oxygen species ,Organic Chemistry ,JNK Mitogen-Activated Protein Kinases ,Antioxidant Response Elements ,Heme oxygenase ,lcsh:Biology (General) ,lcsh:QD1-999 ,chemistry ,Reactive Oxygen Species ,Oxidative stress - Abstract
Sulfuretin is one of the major flavonoid components in Rhus verniciflua Stokes (Anacardiaceae) isolates. In this study, we investigated the protective effects of sulfuretin against tert-butyl hydroperoxide (t-BHP)-induced oxidative injury. The results indicated that the addition of sulfuretin before t-BHP treatment significantly inhibited cytotoxicity and reactive oxygen species (ROS) production in human liver-derived HepG2 cells. Sulfuretin up-regulated the activity of the antioxidant enzyme heme oxygenase (HO)-1 via nuclear factor E2-related factor 2 (Nrf2) translocation into the nucleus and increased the promoter activity of the antioxidant response element (ARE). Moreover, sulfuretin exposure enhanced the phosphorylation of c-Jun N-terminal kinase (JNK) and extracellular signal-regulated kinase 1/2 (ERK1/2), which are members of the mitogen-activated protein kinase (MAPK) family. Furthermore, cell treatment with a JNK inhibitor (SP600125) and ERK inhibitor (PD98059) reduced sulfuretin-induced HO-1 expression and decreased its protective effects. Taken together, these results suggest that the protective effect of sulfuretin against t-BHP-induced oxidative damage in human liver-derived HepG2 cells is attributable to its ability to scavenge ROS and up-regulate the activity of HO-1 through the Nrf2/ARE and JNK/ERK signaling pathways. Therefore, sulfuretin could be advantageous as a bioactive source for the prevention of oxidative injury.
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- 2014
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63. Comparative functional analysis of the velvet gene family reveals unique roles in fungal development and pathogenicity in Magnaporthe oryzae
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Yong-Hwan Lee, Kyoung Su Kim, Hyo Jung Kim, and Joon-Hee Han
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Magnaporthe ,Genes, Fungal ,Conidiation ,Microbiology ,Genome ,Aspergillus nidulans ,Cell Wall ,Botany ,Genetics ,Gene family ,Gene ,Phylogeny ,Plant Diseases ,Appressorium ,Mycelium ,biology ,Velvet ,Oryza ,Sequence Analysis, DNA ,Spores, Fungal ,biology.organism_classification ,Oxidative Stress ,Multigene Family ,Gene Deletion - Abstract
The ascomycete fungus Magnaporthe oryzae is an economically important pathogen that causes rice blast disease worldwide. Accumulating evidence indicates that the fungal velvet genes are key regulators of a number of cellular processes, including development, pathogenicity and secondary metabolism, in many species of fungi. In this study, we identified and functionally characterized four genes (MoVOSA, MoVELB, MoVEA, and MoVELC) from the genome of the fungal pathogen M. oryzae. These genes were homologous to the velvet gene family of Aspergillus nidulans. Deletions of MoVEA, MoVELB, and MoVELC resulted in a significant decrease in conidiation, indicating their roles as positive regulators thereof. The MoVELC gene was involved in development of conidial morphology, while MoVELB and MoVEA appeared necessary for conidial germination, MoVEA further being indispensable for appressorial development and modulation of reactive oxygen species in disease development. Deletion of MoVELC affected the cell wall integrity of appressoria, resulting in failure to penetrate host cells. Unexpectedly, MoVOSA appeared dispensable for the development and pathogenicity of M. oryzae, even though its homologs play specific roles in other fungal species. Taken together, our data demonstrate that the velvet genes are linked to M. oryzae infection-related development and pathogenicity, and the findings provide a framework for comparative studies of the conserved velvet gene family across a range of fungal taxa, which may provide new insight into fungal development and pathogenicity.
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- 2014
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64. The Neoflavonoid Latifolin Isolated from MeOH Extract ofDalbergia odoriferaAttenuates Inflammatory Responses by Inhibiting NF-κB ActivationviaNrf2-Mediated Heme Oxygenase-1 Expression
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Youn-Chul Kim, Bin Li, Gil-Saeng Jeong, Samell Keo, Dong-Sung Lee, Kyoung Su Kim, Wonmin Ko, and Hyuncheol Oh
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Pharmacology ,biology ,Lipopolysaccharide ,Inflammation ,NFKB1 ,Neoflavonoid ,Proinflammatory cytokine ,Nitric oxide synthase ,Heme oxygenase ,chemistry.chemical_compound ,chemistry ,Biochemistry ,medicine ,biology.protein ,Tumor necrosis factor alpha ,medicine.symptom - Abstract
In Korea and China, the heartwood of Dalbergia odorifera T. Chen is an important traditional medicine used to treat blood disorders, ischemia, swelling, and epigastric pain. In this study, we investigated the inhibitory effects of latifolin, a major neoflavonoid component isolated from the MeOH extract of D. odorifera, on the inflammatory reaction of thioglycollate-elicited peritoneal macrophages exposed to lipopolysaccharide, with a particular focus on heme oxygenase-1 (HO-1) expression and nuclear factor-κB (NF-κB) signaling. Latifolin significantly inhibited the protein and mRNA expression of inducible nitric oxide synthase and COX-2, reduced NO, prostaglandins E2, tumor necrosis factor-α, and interleukin-1β production in primary murine peritoneal macrophages exposed to lipopolysaccharide. Latifolin also suppressed inhibitor κB-α levels, NF-κB nuclear translocation, and NF-κB DNA-binding activity. Furthermore, latifolin upregulated HO-1 expression via nuclear transcription factor-E2-related factor 2 (Nrf2) nuclear translocation. In addition, using inhibitor tin protoporphyrin IX (SnPP), an inhibitor of HO-1, it was verified that the inhibitory effects of latifolin on the proinflammatory mediators and NF-κB DNA-binding activity were associated with the HO-1 expression. These results suggested that the latifolin-mediated up-regulation of HO-1 expression played a critical role in anti-inflammatory effects in macrophages. This study therefore identified potent therapeutic effects of latifolin, which warrants further investigation as a potential treatment for inflammatory diseases.
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- 2014
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65. The inhibition of JNK MAPK and NF-κB signaling by tenuifoliside A isolated from Polygala tenuifolia in lipopolysaccharide-induced macrophages is associated with its anti-inflammatory effect
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Ho Sub Lee, Dong-Sung Lee, Kyoung Su Kim, Hyuncheol Oh, Dae-Gil Kang, Gi-Sang Bae, Youn-Chul Kim, and Sung-Joo Park
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Lipopolysaccharides ,MAPK/ERK pathway ,Polygala ,Lipopolysaccharide ,Cell Survival ,Active Transport, Cell Nucleus ,Anti-Inflammatory Agents ,Nitric Oxide Synthase Type II ,Inflammation ,Pharmacology ,Biology ,Disaccharidases ,Nitric oxide ,Mice ,chemistry.chemical_compound ,medicine ,Animals ,RNA, Messenger ,Cell Nucleus ,Kinase ,JNK Mitogen-Activated Protein Kinases ,NF-kappa B ,DNA ,biology.organism_classification ,I-kappa B Kinase ,Nitric oxide synthase ,chemistry ,Biochemistry ,Cyclooxygenase 2 ,Polygala tenuifolia ,Macrophages, Peritoneal ,biology.protein ,Cytokines ,Tumor necrosis factor alpha ,medicine.symptom ,Signal Transduction - Abstract
The root of Polygala tenuifolia Willd. (Polygalaceae) is well known for its use in the treatment of neurasthenia, amnesia, and inflammation. In this study, we isolated phenyl propanoid type metabolite tenuifoliside A, one of the phenylpropanoids from P. tenuifolia, and investigated its anti-inflammatory effects in lipopolysaccharide (LPS)-stimulated RAW264.7 and murine peritoneal macrophages. The results showed that tenuifoliside A inhibited the production of nitric oxide (NO), inducible nitric oxide synthase (iNOS), prostaglandin E2 (PG E2), and cyclooxygenase (COX)-2. In addition, tenuifoliside A suppressed the production of pro-inflammatory cytokines, such as tumor necrosis factor (TNF)-α and interleukin (IL)-1β. We also evaluated the effects of tenuifoliside A on the activation of nuclear factor-kappaB (NF-κB). Tenuifoliside A inhibited the translocation of the NF-κB subunit p65 into the nucleus by interrupting the phosphorylation and degradation of inhibitor kappa B (IκB)-α in LPS-stimulated murine peritoneal macrophages. Moreover, we confirmed that the suppression of the inflammatory process by tenuifoliside A was mediated through the mitogen-activated protein kinases (MAPKs) pathway based on the fact that tenuifoliside A significantly decreased p-c-Jun N-terminal kinase (p-JNK) protein expression in LPS-stimulated murine peritoneal macrophages. Taken together, the anti-inflammatory effects of tenuifoliside A were mediated by the inhibition of the NF-κB and MAPK pathways. This study is the first report on the anti-inflammatory effects of tenuifoliside A, and the strong anti-inflammatory effects of tenuifoliside A provide potential compound to be developed as therapeutic for inflammatory diseases.
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- 2013
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66. A new sulfonic acid derivative, (Z)-4-methylundeca-1,9-diene-6-sulfonic acid, isolated from the cold water sea urchin inhibits inflammatory responses through JNK/p38 MAPK and NF-κB inactivation in RAW 264.7
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Il Chan Kim, Youn-Chul Kim, Wonmin Ko, Hyuncheol Oh, Kyoung Su Kim, Xiang Cui, Ren-Bo An, Joung Han Yim, and Dong-Sung Lee
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MAPK/ERK pathway ,Cell Survival ,MAP Kinase Kinase 4 ,MAP Kinase Signaling System ,Oceans and Seas ,p38 mitogen-activated protein kinases ,Blotting, Western ,Anti-Inflammatory Agents ,Sulfonic acid ,Nitric Oxide ,p38 Mitogen-Activated Protein Kinases ,Cell Line ,Mice ,chemistry.chemical_compound ,biology.animal ,Drug Discovery ,Animals ,Sea urchin ,chemistry.chemical_classification ,biology ,Chemistry ,Macrophages ,Organic Chemistry ,NF-kappa B ,NF-κB ,Cold Temperature ,Alkanesulfonic Acids ,Biochemistry ,Sea Urchins ,Mitogen-activated protein kinase ,biology.protein ,Molecular Medicine ,Phosphorylation ,Sulfonic Acids ,Derivative (chemistry) - Abstract
In this study, we isolated a new sulfonic acid derivative, (Z)-4-methylundeca-1,9-diene-6-sulfonic acid (1), from the sea urchin collected from the Sea of Okhotsk. We established the structure of this new compound by analysis of NMR and HRMS data, along with comparison of the data with those of the related compounds reported in the literature. In addition, we investigated its anti-inflammatory effects in LPS-stimulated RAW264.7 macrophages. Compound 1 inhibited the production of NO, iNOS, PGE2, and COX-2, and it also suppressed the production of pro-inflammatory cytokines, such as TNF-α and IL-1β. It inhibited the translocation of the NF-κB subunit p65 into the nucleus by interrupting the phosphorylation and degradation of IκB-α. In addition, compound 1 significantly decreased the phosphorylation of JNK and p38 in LPS-stimulated RAW264.7 macrophages, suggesting that suppression of the inflammation process by compound 1 was mediated through the MAPK pathway. Taken together, this study showed that the anti-inflammatory effects of a new sulfonic acid derivative, (Z)-4-methylundeca-1,9-diene-6-sulfonic acid were mediated through the inhibition of NF-κB and JNK/p38 MAPK signaling pathways.
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- 2013
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67. Penicillinolide A: A New Anti-Inflammatory Metabolite from the Marine Fungus Penicillium sp. SF-5292
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Jong Seog Ahn, Youn-Chul Kim, Dong-Sung Lee, Tran Hong Quang, Jae-Hyuk Jang, Kyoung Su Kim, Jae Hak Sohn, Wonmin Ko, and Hyuncheol Oh
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NF-E2-Related Factor 2 ,medicine.drug_class ,Metabolite ,Interleukin-1beta ,Anti-Inflammatory Agents ,Penicillium sp ,marine-derived fungi ,10-membered lactone ,anti-inflammatory effect ,heme oxygenase-1 ,Pharmaceutical Science ,Nitric Oxide ,Dinoprostone ,Article ,Anti-inflammatory ,Nitric oxide ,Lactones ,Mice ,chemistry.chemical_compound ,NF-KappaB Inhibitor alpha ,Drug Discovery ,medicine ,Animals ,Phosphorylation ,Pharmacology, Toxicology and Pharmaceutics (miscellaneous) ,lcsh:QH301-705.5 ,Cells, Cultured ,Marine fungi ,chemistry.chemical_classification ,biology ,Interleukin-6 ,Tumor Necrosis Factor-alpha ,NF-kappa B ,Penicillium ,biology.organism_classification ,NFKB1 ,Mice, Inbred C57BL ,Biochemistry ,chemistry ,lcsh:Biology (General) ,Macrophages, Peritoneal ,I-kappa B Proteins ,Lactone - Abstract
In the course of studies on bioactive metabolites from marine fungi, a new 10-membered lactone, named penicillinolide A (1) was isolated from the organic extract of Penicillium sp. SF-5292 as a potential anti-inflammatory compound. The structure of penicillinolide A (1) was mainly determined by analysis of NMR and MS data and Mosher's method. Penicillinolide A (1) inhibited the production of NO and PGE(2) due to inhibition of the expression of iNOS and COX-2. Penicillinolide A (1) also reduced TNF-alpha, IL-1 beta and IL-6 production, and these anti-inflammatory effects were shown to be correlated with the suppression of the phosphorylation and degradation of I kappa B-alpha, NF-kappa B nuclear translocation, and NF-kappa B DNA binding activity. In addition, using inhibitor tin protoporphyrin (SnPP), a competitive inhibitor of HO activity, it was verified that the inhibitory effects of compound 1 on the production of pro-inflammatory mediators and NF-kappa B DNA binding activity were partially associated with HO-1 expression through Nrf2 nuclear translocation.
- Published
- 2013
68. Antifungal Activity of Bacillus sp. GJ-1 Against Phytophthora capsici
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Joon-Hee Han, Heung Tae Kim, Gun-Joo Lee, Kyoung Su Kim, and Jong-Hwan Shin
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Rhizosphere ,Ecology ,biology ,fungi ,food and beverages ,Plant Science ,biology.organism_classification ,Pythium ultimum ,Microbiology ,Fungicide ,Rhizoctonia solani ,Phytophthora capsici ,Pepper ,Blight ,Fusarium solani ,Ecology, Evolution, Behavior and Systematics - Abstract
Phytophthora capsici is one of major limiting factors in production of pepper and other important crops worldwide by causing foliage blight and rot on fruit and root. Increased demand for the replacement of fungicides has led to searching a promising strategy to control the fungal diseases. To meet eco-friendly agriculture practice, we isolated microorganisms and assessed their beneficial effects on plant health and disease control efficacy. A total of 360 bacterial strains were isolated from rhizosphere soil of healthy pepper plants, and categorized to 5 representative isolates based on colony morphology. Among the 5 bacterial strains (GJ-1, GJ-4, GJ-5, GJ-11, GJ-12), three bacterial strains (GJ-1, GJ-11, GJ-12) presented antifungal activity against P. capsici in an fungal inhibition assay. In phosphate solubilization and siderophore production, the strain GJ-1 was more effective than others. The strain GJ-1 was identified as Bacillus sp. using 16S rDNA analysis. Bacillus sp. GJ-1 was also found to be effective in inhibiting other plant pathogenic fungi, including Rhizoctonia solani, Pythium ultimum and Fusarium solani. Therefore, the Bacillus sp. GJ-1 can serve as a biological control agent against fungal plant pathogens.
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- 2013
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69. Butein protects human dental pulp cells from hydrogen peroxide-induced oxidative toxicity via Nrf2 pathway-dependent heme oxygenase-1 expressions
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Dong-Sung Lee, Youn-Chul Kim, Eun-Cheol Kim, Kyoung Su Kim, Bin Li, and Gil-Saeng Jeong
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Programmed cell death ,Necrosis ,Cell Survival ,NF-E2-Related Factor 2 ,Oxidative phosphorylation ,Pharmacology ,Toxicology ,medicine.disease_cause ,Antioxidants ,Cell Line ,chemistry.chemical_compound ,Chalcones ,medicine ,Humans ,Cytotoxicity ,Dental Pulp ,Butein ,chemistry.chemical_classification ,Reactive oxygen species ,Hydrogen Peroxide ,General Medicine ,Heme oxygenase ,Oxidative Stress ,chemistry ,Biochemistry ,Mitogen-Activated Protein Kinases ,medicine.symptom ,Reactive Oxygen Species ,Heme Oxygenase-1 ,Oxidative stress - Abstract
Rhus verniciflua Stokes is a plant that is native to East Asian countries, such as Korea, China, and Japan. Butein, a plant polyphenol, is one of the major active components of R. verniciflua. Reactive oxygen species (ROS), produced via dental adhesive bleaching agents and pulpal disease, can cause oxidative stress. Here, we found that butein possesses cytoprotective effects on hydrogen peroxide (H2O2)-induced dental cell death. H2O2 is a representative ROS and causes cell death through necrosis in human dental pulp (HDP) cells. H2O2-induced cytotoxicity and production of ROS were blocked in the presence of butein, and these effects were dose dependent. Butein also increased heme oxygenase-1 (HO-1) protein expression and HO activity. In addition, butein-dependent HO-1 expression was required for the inhibition of H2O2-induced cell death and ROS generation. Furthermore, butein treatment caused nuclear accumulation of nuclear factor-E2-related factor 2 (Nrf2) and increased the promoter activity of antioxidant response elements (AREs). Treatment of HDP cells with a c-Jun NH2-terminal kinase (JNK) inhibitor also reduced butein-induced HO-1 expression, and butein treatment led to increased JNK phosphorylation. These results indicate that butein may be used to prevent functional dental cell death and thus may be useful as a pulpal disease agent.
- Published
- 2013
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70. RNA-seq of life stages of the oomycete Phytophthora infestans reveals dynamic changes in metabolic, signal transduction, and pathogenesis genes and a major role for calcium signaling in development
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Audrey M. V. Ah-Fong, Howard S. Judelson, and Kyoung Su Kim
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0106 biological sciences ,0301 basic medicine ,Hypha ,Bioinformatics ,1.1 Normal biological development and functioning ,Medical and Health Sciences ,01 natural sciences ,Spore development ,Transcriptome ,03 medical and health sciences ,Oomycete ,Underpinning research ,Information and Computing Sciences ,Sporogenesis ,Zoospore ,Genetics ,Cluster Analysis ,Calcium Signaling ,Transcriptomics ,Gene ,biology ,Microarray analysis techniques ,Sporangium ,Gene Expression Profiling ,Human Genome ,fungi ,Calcium-Binding Proteins ,Computational Biology ,High-Throughput Nucleotide Sequencing ,Molecular Sequence Annotation ,Biological Sciences ,biology.organism_classification ,Gene regulation ,Infectious Diseases ,030104 developmental biology ,Gene Ontology ,Gene Expression Regulation ,Oomycetes ,Phytophthora infestans ,Energy Metabolism ,010606 plant biology & botany ,Biotechnology ,Signal Transduction ,Research Article - Abstract
Background The oomycete Phytophthora infestans causes the devastating late blight diseases of potato and tomato. P. infestans uses spores for dissemination and infection, like many other filamentous eukaryotic plant pathogens. The expression of a subset of its genes during spore formation and germination were studied previously, but comprehensive genome-wide data have not been available. Results RNA-seq was used to profile hyphae, sporangia, sporangia undergoing zoosporogenesis, motile zoospores, and germinated cysts of P. infestans. Parallel studies of two isolates generated robust expression calls for 16,000 of 17,797 predicted genes, with about 250 transcribed in one isolate but not the other. The largest changes occurred in the transition from hyphae to sporangia, when >4200 genes were up-regulated. More than 1350 of these were induced >100-fold, accounting for 26% of total mRNA. Genes encoding calcium-binding proteins, cation channels, signaling proteins, and flagellar proteins were over-represented in genes up-regulated in sporangia. Proteins associated with pathogenicity were transcribed in waves with subclasses induced during zoosporogenesis, in zoospores, or in germinated cysts. Genes involved in most metabolic pathways were down-regulated upon sporulation and reactivated during cyst germination, although there were exceptions such as DNA replication, where transcripts peaked in zoospores. Inhibitor studies indicated that the transcription of two-thirds of genes induced during zoosporogenesis relied on calcium signaling. A sporulation-induced protein kinase was shown to bind a constitutive Gβ-like protein, which contributed to fitness based on knock-down analysis. Conclusions Spore formation and germination involves the staged expression of a large subset of the transcriptome, commensurate with the importance of spores in the life cycle. A comparison of the RNA-seq results with the older microarray data indicated that information is now available for about twice the number of genes than before. Analyses based on function revealed dynamic changes in genes involved in pathogenicity, metabolism, and signaling, with diversity in expression observed within members of multigene families and between isolates. The effects of calcium signaling, a spore-induced protein kinase, and an interacting Gβ-like protein were also demonstrated experimentally. The results reveal aspects of oomycete biology that underly their success as pathogens and potential targets for crop protection chemicals. Electronic supplementary material The online version of this article (doi:10.1186/s12864-017-3585-x) contains supplementary material, which is available to authorized users.
- Published
- 2016
71. Corrigendum to 'Inhibitory effect of 9-hydroxy-6,7-dimethoxydalbergiquinol from Dalbergia odorifera on the NF-кB-related neuroinflammatory response in lipopolysaccharide-stimulated mouse BV2 microglial cells is mediated by heme oxygenase-1' [Int Immunopharmacol (2013) 828-835]
- Author
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Gil-Saeng Jeong, Samell Keo, Hyuncheol Oh, Dong-Sung Lee, Bin Li, Kyoung Su Kim, and Youn-Chul Kim
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Pharmacology ,Lipopolysaccharide ,biology ,Stereochemistry ,Immunology ,INT ,biology.organism_classification ,Molecular biology ,Heme oxygenase ,chemistry.chemical_compound ,Dalbergia ,chemistry ,Immunology and Allergy ,Inhibitory effect - Published
- 2016
72. Anti-Inflammatory Effects and Mechanisms of Action of Coussaric and Betulinic Acids Isolated from Diospyros kaki in Lipopolysaccharide-Stimulated RAW 264.7 Macrophages
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Hyuncheol Oh, Wonmin Ko, Dong-Cheol Kim, Kyoung-Su Kim, Dong-Sung Lee, Youn-Chul Kim, and Chi-Su Yoon
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0301 basic medicine ,Lipopolysaccharides ,Lipopolysaccharide ,betulinic acid (BA) ,Anti-Inflammatory Agents ,Pharmaceutical Science ,Analytical Chemistry ,chemistry.chemical_compound ,Mice ,0302 clinical medicine ,Diospyros kaki Thunb ,Betulinic acid ,Drug Discovery ,biology ,NF-kappa B ,heme oxygenase-1 ,Nitric oxide synthase ,Biochemistry ,Chemistry (miscellaneous) ,030220 oncology & carcinogenesis ,Molecular Medicine ,Tumor necrosis factor alpha ,Pentacyclic Triterpenes ,Prostaglandin ,Nitric Oxide ,Dinoprostone ,Article ,Nitric oxide ,lcsh:QD241-441 ,03 medical and health sciences ,lcsh:Organic chemistry ,Animals ,coussaric acid (CA) ,Physical and Theoretical Chemistry ,Betulinic Acid ,nuclear factor-kappa B ,Monokines ,Organic Chemistry ,Diospyros kaki ,Membrane Proteins ,anti-inflammation ,Diospyros ,Molecular biology ,Triterpenes ,Heme oxygenase ,030104 developmental biology ,RAW 264.7 Cells ,chemistry ,Cyclooxygenase 2 ,biology.protein - Abstract
Diospyros kaki Thunb. is widely distributed in East Asian countries, its leaves being mainly used for making tea. In this study, coussaric acid (CA) and betulinic acid (BA), both triterpenoid compounds, were obtained from D. kaki leaf extracts through bioassay-guided isolation. CA and BA showed anti-inflammatory effects via inhibition of the nuclear factor-κB (NF-κB) pathway, providing important information on their anti-inflammatory mechanism. Furthermore, they markedly inhibited nitric oxide (NO) and prostaglandin E₂ (PGE₂) production in lipopolysaccharide (LPS)-activated RAW 264.7 macrophages, and suppressed tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and interleukin-1β (IL-1β) levels. Furthermore, they decreased protein expression of inducible nitric oxide synthase and cyclooxygenase-2. Pre-treatment with CA and BA inhibited LPS-induced NF-κB. We further examined the effects of CA and BA on heme oxygenase (HO)-1 expression in RAW 264.7 macrophages: BA induced HO-1 protein expression in a dose-dependent manner, while CA had no effect. We also investigated whether BA treatment induced nuclear translocation of Nrf2. BA inhibited LPS-induced NF-κB-binding activity, as well as pro-inflammatory mediator and cytokine production (e.g., NO, PGE₂, TNF-α, IL-1β, IL-6), by partial reversal of this effect by SnPP, an inhibitor of HO-1. These findings further elucidate the anti-inflammatory mechanism of CA and BA isolated from D. kaki.
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- 2016
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73. The CuZn superoxide dismutase from Sclerotinia sclerotiorum is involved with oxidative stress tolerance, virulence, and oxalate production
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Selvakumar Veluchamy, Brett Williams, Kyoung Su Kim, and Martin B. Dickman
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chemistry.chemical_classification ,Hyphal growth ,Reactive oxygen species ,biology ,Superoxide ,070300 CROP AND PASTURE PRODUCTION ,Superoxide dismutase, Oxalate, Sclerotinia sclerotioum, Oxidative stress tolerance, Reactive oxygen species ,Sclerotinia sclerotiorum ,060700 PLANT BIOLOGY ,Virulence ,060500 MICROBIOLOGY ,Plant Science ,biology.organism_classification ,medicine.disease_cause ,Microbiology ,Respiratory burst ,Superoxide dismutase ,chemistry.chemical_compound ,chemistry ,Biochemistry ,Genetics ,biology.protein ,medicine ,Oxidative stress - Abstract
One of the earliest plant responses to pathogens is the induced accumulation of reactive oxygen species (ROS). The superoxide ion is an important intermediate in the generation of ROS having a key regulatory function during plant–microbe interactions and is an important component in fungal development. The superoxide dismutase (SOD) family contributes to frontline defense via detoxification of reactive superoxide radical anions. Sclerotinia sclerotiorum (Lib.) de Bary is a necrotrophic fungal pathogen with a broad host range. S. sclerotiorum produces the non-specific phytotoxin and key pathogenicity factor, oxalic acid (OA). We have identified an S. sclerotiorum SOD (Sssod1) with high similarity to CuZnSODs. Sssod1 contains an open reading frame of 908 bp in length and is predicted to encode a protein of 155 amino acids that harbors the entire hallmark motifs associated with SOD function. Treatment with the CuZnSOD inhibitor diethyldithiocarbamate (DETC) resulted in delayed hyphal growth and sclerotial development in a dose-dependent manner. Mutants generated carrying an Sssod1 deletion (ΔSssod1) exhibited morphological defects similar to those observed with the inhibitor treatment. Moreover, ΔSssod1 was more sensitive than wild-type to menadione, a redox cycling agent. Expression of Sssod1 was induced following treatment with oxidizing agents and during interaction with plant host tissue the ΔSssod1 mutant was significantly reduced in virulence on both tomato and tobacco plants compared to wild-type. Interestingly, pathogenicity of the superoxide dismutase mutant was mostly restored following supplementation with oxalate. We also observed that ΔSssod1 was reduced in oxalate production by half. In accordance with reduced virulence, ΔSssod1 induced a host oxidative burst in adjacent uninfected cells, a phenotype indicative of active pathogen recognition by the host. Intriguingly, during wild-type infection, host ROS production was significantly reduced. These results suggest that wild-type Sclerotinia suppresses host defense responses during infection.
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- 2012
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74. The cell cycle gene MoCDC15 regulates hyphal growth, asexual development and plant infection in the rice blast pathogen Magnaporthe oryzae
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Jaejin Park, Jaeduk Goh, Kyoung Su Kim, Yong-Hwan Lee, Junhyun Jeon, and Sook-Young Park
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Hyphal growth ,Molecular Sequence Data ,Mutant ,Hyphae ,Conidiation ,Cell Cycle Proteins ,Biology ,Microbiology ,Fungal Proteins ,GTP-Binding Proteins ,Gene Expression Regulation, Fungal ,Genetics ,Amino Acid Sequence ,Gene ,Pathogen ,Plant Diseases ,Wild type ,food and beverages ,Oryza ,Sequence Analysis, DNA ,Phenotype ,Yeast ,Cell biology ,Genes, cdc ,Magnaporthe ,Mutation ,Sequence Alignment - Abstract
Rice blast, caused by the pathogen Magnaporthe oryzae, is a serious hindrance to rice production and has emerged as an important model for the characterization of molecular mechanisms relevant to pathogenic development in plants. Similar to other pathogenic fungi, conidiation plays a central role in initiation of M. oryzae infection and spread over a large area. However, relatively little is known regarding the molecular mechanisms that underlie conidiation in M. oryzae. To better characterize these mechanisms, we identified a conidiation-defective mutant, ATMT0225B6 (MoCDC15T-DNA), in which a T-DNA insertion disrupted a gene that encodes a homolog of fission yeast cdc15, and generated a second strain containing a disruption in the same allele (ΔMoCDC15T-DNA). The cdc15 gene has been shown to act as a coordinator of the cell cycle in yeast. Functional analysis of the MoCDC15T-DNA and ΔMoCDC15T-DNA mutants revealed that MoCDC15 is required for conidiation, preinfection development and pathogenicity in M. oryzae. Conidia from these mutants were viable, but failed to adhere to hydrophobic surface, a crucial step required for subsequent pathogenic development. All phenotypic defects observed in mutants were rescued in a strain complemented with wild type MoCDC15. Together, these data indicate that MoCDC15 functions as a coordinator of several biological processes important for pathogenic development in M. oryzae.
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- 2011
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75. Hydraulic Fracture Design with a Proxy Model for Unconventional Shale Gas Reservoir with Considering Feasibility Study
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Jonggeun Choe and Kyoung Su Kim
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Control and Optimization ,Shale gas ,production optimization ,020209 energy ,Energy Engineering and Power Technology ,02 engineering and technology ,lcsh:Technology ,hydraulic fracture design ,unconventional shale gas ,proxy model ,Proxy (climate) ,Hydraulic fracturing ,Natural gas ,0202 electrical engineering, electronic engineering, information engineering ,Low permeability ,Electrical and Electronic Engineering ,Engineering (miscellaneous) ,Petroleum engineering ,lcsh:T ,Renewable Energy, Sustainability and the Environment ,business.industry ,020208 electrical & electronic engineering ,Directional drilling ,Economic feasibility ,Environmental science ,business ,Oil shale ,Energy (miscellaneous) - Abstract
Shale gas is a natural gas trapped in shale formation and is being actively developed in North America. Due to the low permeability of a shale gas reservoir in the range from 10−8 to 10−6 Darcy, horizontal drilling and multi-stage hydraulic fracturing are needed for its development. This paper presents a fast and reliable proxy model to forecast shale gas productions and an optimum hydraulic fracturing design for its development. The proxy model uses a robust regression scheme and can replace a commercial reservoir simulator. The proxy model proposed can determine the influence of impact factors on the production at each production time. The calculation speed of the proposed proxy model is about 1.4 million times faster than that of a reservoir simulator compared. The most economical hydraulic fracture design using the proxy model has a length of 168 m at each stage, which is determined by examining a large number of hydraulic fracturing designs considering economic feasibility.
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- 2019
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76. The Effect of Nano-Silver Liquid against the White Rot of the Green Onion Caused by Sclerotium cepivorum
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Youn Su Lee, Kyoung Su Kim, Kim Young Jae, Ji-Seon Min, Sang Woo Kim, Kabir Lamsal, and Jin-Hee Jung
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Sclerotium ,education.field_of_study ,biology ,Green onion ,Population ,Silver Nano ,Greenhouse ,Biomass ,food and beverages ,Soil microbes ,biology.organism_classification ,Microbiology ,Nano-silver ,Horticulture ,Sclerotium cepivorum ,Infectious Diseases ,Botany ,White rot ,Soil composition ,education ,Bacteria ,Research Article - Abstract
White rot, which is caused by Sclerotium cepivorum, is a lethal disease affecting green onions. Three different types of nano-silver liquid (WA-CV-WA13B, WA-AT-WB13R, and WA-PR-WB13R) were tested in several different concentrations on three types of media to assess their antifungal activities. Results from in vitro experiments showed that all three of the nano-silver liquids had more than 90% inhibition rates at a concentration of 7 ppm. Greenhouse experiments revealed that all of the nano-silver liquids increased biomass and dry weights, and there were minimal changes in the population of various bacteria and fungi from the soil of greenhouse-cultivated green onions. In addition, a soil chemical analysis showed that there were minimal changes in soil composition.
- Published
- 2010
77. A Short-chain Dehydrogenase/reductase Gene is Required for Infection-related Development and Pathogenicity in Magnaporthe oryzae
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Yong-Hwan Lee, Kyoung Su Kim, and Min Jung Kwon
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Transfer DNA ,Genetics ,Appressorium ,Short-chain dehydrogenase ,Mutant ,food and beverages ,Conidiation ,Dehydrogenase ,Biology ,Reductase ,Agronomy and Crop Science ,Gene - Abstract
The phytopathogenic fungus Magnaporthe oryzae is a major limiting factor in rice production. To understand the genetic basis of M. oryzae pathogenic development, we previously analyzed a library of T-DNA insertional mutants of M. oryzae, and identified ATMT0879A1 as one of the pathogenicity-defective mutants. Molecular analyses and database searches revealed that a single TDNA insertion in ATMT0879A1 resulted in functional interference with an annotated gene, MGG00056, which encodes a short-chain dehydrogenase/reductase (SDR). The mutant and annotated gene were designated as MoSDR1T-DNA and MoSDR1, respectively. Like other SDR family members, MoSDR1 possesses both a cofactor- binding motif and a catalytic site. The expression pattern of MoSDR1 suggests that the gene is associated with pathogenicity and plays an important role in M. oryzae development. To understand the roles of MoSDR1, the deletion mutant ΔMosdr1 for the gene was obtained via homology-dependent gene replacement. As expected, ΔMosdr1 was nonpathogenic; moreover, the mutant displayed pleiotropic defects in conidiation, conidial germination, appressorium formation, penetration, and growth inside host tissues. These results suggest that MoSDR1 functions as a key metabolic enzyme in the regulation of development and pathogenicity in M. oryzae.
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- 2010
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78. Effects of Colloidal Silver Nanoparticles on Sclerotium-Forming Phytopathogenic Fungi
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Mooyoung Jung, Jin Hee Jung, Seung Bin Kim, Kabir Lamsal, Sang Woo Kim, Kyoung Su Kim, Youn Su Lee, and Ji Seon Min
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Sclerotium ,biology ,Chemical engineering ,medicine ,Nanoparticle ,Colloidal silver ,biology.organism_classification ,medicine.disease_cause ,Agronomy and Crop Science ,Escherichia coli ,Bacteria ,Silver nanoparticle ,Microbiology - Published
- 2009
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79. Antioxidant and Antimicrobial Activities of Extracts from a Medicinal Plant, Sea Buckthorn
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Myong Jo Kim, Yong Soo Kwon, Ji Won Lee, Ju-Sung Kim, Chang Yeon Yu, Sang No Han, Ju Kyong Lee, Jong Hyun Jeong, and Kyoung Su Kim
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Antioxidant ,food.ingredient ,biology ,DPPH ,medicine.medical_treatment ,Food additive ,Organic Chemistry ,Ethyl acetate ,Hippophae rhamnoides ,Antimicrobial ,Ascorbic acid ,biology.organism_classification ,General Biochemistry, Genetics and Molecular Biology ,Superoxide dismutase ,chemistry.chemical_compound ,food ,chemistry ,Biochemistry ,medicine ,biology.protein ,Food science - Abstract
This study was performed to evaluate the antioxidant and antimicrobial activities from the methanol extracts of the root and stem of Hippophae rhamnoides and their further partitioned fractions including hexane, ethyl acetate, butanol, and water. Antioxidant activities of the plant parts were measured by l,l-dephenyl-2-picryl-hydrazyl (DPPH), superoxide dismutase (SOD)-like activity, and ferric thiocyanate (FTC) assays, and compared to standard antioxidants of butylated hydroxyl anisole, butylated hydroxyl toluene, a-tocopherol, and ascorbic acid. Antimicrobial activity of the plant extracts and fractions were evaluated by determining the minimum inhibitory concentration values. DPPH assay showed that the overall strong antioxidant activities from the methanol extracts and fractions. The values of SOD-like activities in hexane fractions of the root and stem were close to the measurement of a reference, ascorbic acid at 1,000 ppm. The methanol extract of the root in FTC assay showed a remarkable antioxidant and free radical scavenging activity. The extracts and fractions of the root and stem showed better antimicrobial activity than compared antimicrobial agents, (+)-catechin, ketoconazol, and mycostantin. This study indicates that the plant root and stem contain a variety of compounds contributing to antioxidant and antimicrobial activity, which could be used for food additives and the development of useful natural compounds.
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- 2009
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80. The complete mitochondrial genome sequence of the ascomycete plant pathogen Colletotrichum acutatum
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Ki-Young Choi, Joon-Hee Han, Ik-Young Choi, Kyoung Su Kim, Yong-Hwan Lee, and Joon-Oh Kim
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0106 biological sciences ,0301 basic medicine ,Mitochondrial DNA ,Biology ,01 natural sciences ,Genome ,DNA, Mitochondrial ,Fungal Proteins ,03 medical and health sciences ,Open Reading Frames ,Colletotrichum acutatum ,RNA, Transfer ,Genetics ,Colletotrichum ,Molecular Biology ,Gene ,Phylogeny ,Fungal protein ,Base Composition ,Sequence Analysis, DNA ,Plants ,biology.organism_classification ,Stop codon ,Open reading frame ,030104 developmental biology ,RNA, Ribosomal ,Transfer RNA ,Genome, Mitochondrial ,010606 plant biology & botany - Abstract
Collectotrichum acutatum is a fungal plant pathogen that causes pre- and post-harvest anthracnose on a wide range of plants worldwide. The complete mitochondrial genome of C. acutatum has been determined for the first time. This study revealed that the mitogenome of C. acutatum is a closed circular molecule of 30 892 bp in length, with a G + C content of 34.7%, which include 15 protein-coding genes, 22 tRNA genes, and two rRNA genes. All the protein-coding genes, accounting for 46.6% of the C. acutatum mitogenome, start with the standard ATG codon and end with the TAA termination codon except for nad6 gene using the TAG termination codon. The mitogenome information of C. acutatum can provide molecular basis for further studies on molecular systematics and evolutionary dynamics.
- Published
- 2015
81. Antagonistic Activities of Bacillus spp. Strains Isolated from Tidal Flat Sediment Towards Anthracnose Pathogens Colletotrichum acutatum and C. gloeosporioides in South Korea
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Kyoung Su Kim, Jong-Hwan Shin, Joon-Hee Han, and Hong-Sik Shim
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biology ,antifungal activity ,Biological pest control ,biological control ,Articles ,lcsh:Plant culture ,Bacillus atrophaeus ,biology.organism_classification ,Microbiology ,Fungicide ,Colletotrichum ,Colletotrichum acutatum ,Pepper ,Chitinase ,biology.protein ,lcsh:SB1-1110 ,Agronomy and Crop Science ,mudflat ,Bacteria - Abstract
Anthracnose is a fungal disease caused by Colletotrichum species that is detrimental to numerous plant species. Anthracnose control with fungicides has both human health and environmental safety implications. Despite increasing public concerns, fungicide use will continue in the absence of viable alternatives. There have been relatively less efforts to search antagonistic bacteria from mudflats harboring microbial diversity. A total of 420 bacterial strains were isolated from mudflats near the western sea of South Korea. Five bacterial strains, LB01, LB14, HM03, HM17, and LB15, were characterized as having antifungal properties in the presence of C. acutatum and C. gloeosporioides. The three Bacillus atrophaeus strains, LB14, HM03, and HM17, produced large quantities of chitinase and protease enzymes, whereas the B. amyloliquefaciens strain LB01 produced protease and cellulase enzymes. Two important antagonistic traits, siderophore production and solubilization of insoluble phosphate, were observed in the three B. atrophaeus strains. Analyses of disease suppression revealed that LB14 was most effective for suppressing the incidence of anthracnose symptoms on pepper fruits. LB14 produced antagonistic compounds and suppressed conidial germination of C. acutatum and C. gloeosporioides. The results from the present study will provide a basis for developing a reliable alternative to fungicides for anthracnose control.
- Published
- 2015
82. A Study on the Ball-off of Via Balls Bonded by Solder Paste
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Kyoung-Su Kim and Jin-Young Kim
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Materials science ,Optical microscope ,Scanning electron microscope ,law ,Soldering ,Ball grid array ,Metallurgy ,Screen printing ,Intermetallic ,Solder paste ,Fatigue limit ,law.invention - Abstract
Package reliability test was conducted to investigate the effect of solder paste composition at BGA Package. It was found that the shape and size of the phase form are affected by the processing parameters. The material have used to fill in the via was Sn/36Pb/2Ag and Sn/0.75Cu type solder paste. Sn/36Pb/2Ag and Sn/0.75Cu paste were fabricated on Tape-BGA substrates by screen printing process, and via ball mount data were characterized with variations of dwell time of 85 seconds at reflow peak temperature at 22 or 24. The test condition was MRT 30 /60 %RH/96 HR. Failures formed of a ball-off in solder paste process were observed by using a Optical Microscope and SEM(Scanning Electron Microscope). It was concluded that intermetallic layer growth played important roles in increasing solder fatigue strength for addition of Ag composition. The degradation of shear strength of solder composition is discussed.
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- 2004
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83. Effects of mutations in the N terminal region of the yeast G protein α-subunit Gpa1p on signaling by pheromone receptors
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Kyoung Su Kim, Mark E. Dumont, M. Roginskaya, S. M. Connelly, and D. Patel
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Saccharomyces cerevisiae Proteins ,Gs alpha subunit ,GTPase-activating protein ,G protein ,Immunoblotting ,Mutation, Missense ,Saccharomyces cerevisiae ,Biology ,Fluorescence ,Fungal Proteins ,Heterotrimeric G protein ,Genetics ,Molecular Biology ,Alleles ,G protein-coupled receptor ,G alpha subunit ,G protein-coupled receptor kinase ,Membrane Proteins ,General Medicine ,GTP-Binding Protein alpha Subunits ,Receptors, Pheromone ,G beta-gamma complex ,Phenotype ,Biochemistry ,Mutagenesis ,GTP-Binding Protein alpha Subunits, Gq-G11 ,Plasmids ,Signal Transduction - Abstract
The sites and modes of interaction between G protein-coupled receptors and their cognate heterotrimeric G proteins remain poorly defined. The C-terminus of the Galpha subunit is the best established site of contact of G proteins with receptors, but structural analyses and crosslinking studies suggest the possibility of interactions at the N-terminus of Galpha as well. We screened for mutations in the N-terminal region of the Galpha subunit encoded by the yeast GPA1 gene that specifically affect the ability of the G protein to be activated by the yeast alpha-mating factor receptor. The screen led to identification of substitutions of glutamine or proline for Leu18 of Gpa1p that reduce the response to the pheromones alpha-factor and a-factor without affecting cellular levels of the subunit or its ability to interact with beta and gamma subunits. The mutations do not appear to affect the intrinsic ability of the G protein to be converted to the activated state. The low yield of different mutations with this phenotype indicates either that the N-terminal segment of the yeast Galpha subunit does not undergo extensive interactions with the alpha-factor receptor, or that this region can not be altered without detrimental effects upon the formation of G protein trimers.
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- 2004
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84. Whole genome sequence and genome annotation of Colletotrichum acutatum, causal agent of anthracnose in pepper plants in South Korea
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Ik-Young Choi, Yong-Hwan Lee, Kyoung Su Kim, Jae-Kyung Chon, Joon-Hee Han, and Jong-Hwa Ahn
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0106 biological sciences ,0301 basic medicine ,Colletotrichum acutatum ,lcsh:QH426-470 ,Gene prediction ,Biology ,01 natural sciences ,Biochemistry ,Genome ,03 medical and health sciences ,Pepper ,Data in Brief ,Genetics ,Ascomycete ,Anthracnose ,Gene ,Whole genome sequencing ,Genome project ,biology.organism_classification ,genomic DNA ,lcsh:Genetics ,030104 developmental biology ,GenBank ,Genome sequence ,Molecular Medicine ,010606 plant biology & botany ,Biotechnology - Abstract
Colletotrichum acutatum is a destructive fungal pathogen which causes anthracnose in a wide range of crops. Here we report the whole genome sequence and annotation of C. acutatum strain KC05, isolated from an infected pepper in Kangwon, South Korea. Genomic DNA from the KC05 strain was used for the whole genome sequencing using a PacBio sequencer and the MiSeq system. The KC05 genome was determined to be 52,190,760bp in size with a G+C content of 51.73% in 27 scaffolds and to contain 13,559 genes with an average length of 1516bp. Gene prediction and annotation were performed by incorporating RNA-Seq data. The genome sequence of the KC05 was deposited at DDBJ/ENA/GenBank under the accession number LUXP00000000.
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- 2016
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85. Sporangium-Specific Gene Expression in theOomycete Phytopathogen Phytophthorainfestans
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Kyoung Su Kim and Howard S. Judelson
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Phytophthora ,L-Iditol 2-Dehydrogenase ,Databases, Factual ,Sorbitol dehydrogenase ,Zoospore ,Genes, Fungal ,Molecular Sequence Data ,Microbiology ,Article ,Fungal Proteins ,Gene Expression Regulation, Fungal ,Cluster Analysis ,Amino Acid Sequence ,RNA, Messenger ,Molecular Biology ,Gene ,Conserved Sequence ,Phylogeny ,Oligonucleotide Array Sequence Analysis ,Solanum tuberosum ,Oomycete ,Genetics ,Base Sequence ,Sequence Homology, Amino Acid ,biology ,Sporangium ,fungi ,Fungal genetics ,Sequence Analysis, DNA ,General Medicine ,Spores, Fungal ,biology.organism_classification ,Phytophthora infestans - Abstract
The oomycete genus Phytophthora includes many of the world's most destructive plant pathogens, which are generally disseminated by asexual sporangia. To identify factors relevant to the biology of these propagules, genes induced in sporangia of the potato late blight pathogen Phytophthora infestans were isolated using cDNA macroarrays. Of ∼1,900 genes known to be expressed in sporangia, 61 were up-regulated >5-fold in sporangia versus hyphae based on the arrays, including 17 that were induced> 100-fold. A subset were also activated by starvation and in a nonsporulating mutant. mRNAs of some genes declined in abundance after germination, while others persisted through the germinated zoospore cyst stage. Functions were predicted for about three-quarters of the genes, including potential regulators (protein kinases and phosphatases, transcription factors, and G-protein subunits), transporters, and metabolic enzymes. Predominant among the last were several dehydrogenases, especially a highly expressed sorbitol dehydrogenase that accounted for 3% of the mRNA. Sorbitol dehydrogenase activity also rose during sporulation and several stress treatments, paralleling the expression of the gene. Another interesting metabolic enzyme resembled creatine kinases, which previously were reported only in animals and trypanosomes. These results provide insight into the transcriptional and cellular processes occurring in sporangia and identify potential targets for crop protection strategies.
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- 2003
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86. Control of Colletotrichum acutatum and Plant Growth Promotion of Pepper by Antagonistic Microorganisms
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김경수 ( Kyoung Su Kim ), 김문종 ( Moon Jong Kim ), and 한준희 ( Joon Hee Han )
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Sweet Peppers ,Soil bacteria ,Plant growth ,Ecology ,Colletotrichum acutatum ,Pepper ,Botany ,Plant Science ,Natural enemies ,Biology ,biology.organism_classification ,Ecology, Evolution, Behavior and Systematics - Abstract
고추 탄저병은 국내 고추재배에 가장 큰 피해를 일으키며, Colletotrichum acutatum이 주요 원인균이다. 본 연구에서는 포장에서 고추탄저병의 방제와 식물생장촉진효과를 선발된 길항미생물을 이용하여 평가하였다. 4개의 길항미생물은 이전 연구를 통하여 고추포장(GJ01, GJ11)과 갯벌(LB01, LB14)에서 선발하였다. 4개의 길항미생물은 대조균주 EXTN-1을 포함하여 C. acutatum과 대치배양에서 길항효과를 보였다. 식물생장촉진효과를 알아보기 위해 고추종자의 발아율과 초기생장효과, 그리고 포장에서 식물의 생장효과를 검정하였다. 그 결과 4개의 선발균주는 모두 식물생장효과가 있었다. 그 중에서도 GJ01은 초기생육에서 가장높은 생장효과를 보였으며, GJ11은 포장에서 가장 높은 고추수확량을 얻었다. 그리고 포장에서 탄저병의 방제효과는 4개의 길항미생물 처리에 의해 63.2~72.5%의 방제가를 보였다. 현재 연구를 토대로 4개의 길항미생물은 고추 탄저병에 대한 잠재적인 생물학적 방제제로서의 가능성을 보여주었다.
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- 2015
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87. Inhibitory Effects of Benzaldehyde Derivatives from the Marine Fungus Eurotium sp. SF-5989 on Inflammatory Mediators via the Induction of Heme Oxygenase-1 in Lipopolysaccharide-Stimulated RAW264.7 Macrophages
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Hyuncheol Oh, Joung Han Yim, Dong-Sung Lee, Youn-Chul Kim, Jae Hak Sohn, Xiang Cui, Ren-Bo An, Wonmin Ko, and Kyoung Su Kim
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Lipopolysaccharides ,Lipopolysaccharide ,Cell Survival ,NF-E2-Related Factor 2 ,Gentisates ,nuclear factor-κB ,Biology ,Catalysis ,Article ,Nitric oxide ,Cell Line ,Inorganic Chemistry ,lcsh:Chemistry ,chemistry.chemical_compound ,Mice ,Eurotium ,Animals ,Eurotium rubrum ,Viability assay ,RNA, Messenger ,Physical and Theoretical Chemistry ,marine fungus ,Molecular Biology ,Heme ,lcsh:QH301-705.5 ,Spectroscopy ,benzaldehyde derivatives ,Macrophages ,Organic Chemistry ,NF-kappa B ,heme oxygenase-1 ,General Medicine ,NFKB1 ,Computer Science Applications ,Heme oxygenase ,Nitric oxide synthase ,Biochemistry ,chemistry ,Gene Expression Regulation ,lcsh:Biology (General) ,lcsh:QD1-999 ,anti-inflammatory effect ,Benzaldehydes ,biology.protein ,Cytokines ,Tumor necrosis factor alpha ,Inflammation Mediators ,RAW264.7 macrophages - Abstract
Two benzaldehyde derivatives, flavoglaucin (1) and isotetrahydro-auroglaucin (2), were isolated from the marine fungus Eurotium sp. SF-5989 through bioassay- and 1H NMR-guided investigation. In this study, we evaluated the anti-inflammatory effects of these compounds in lipopolysaccharide (LPS)-stimulated RAW264.7 macrophages. We demonstrated that compounds 1 and 2 markedly inhibited LPS-induced nitric oxide (NO) and prostaglandin E2 (PGE2) production by suppressing inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) protein expression without affecting cell viability. We also demonstrated that the compounds reduced the secretion of pro-inflammatory cytokines such as tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β) and interleukin-6 (IL-6). Furthermore, compounds 1 and 2 inhibited LPS-induced nuclear factor-κB (NF-κB) activation by suppressing phosphorylation of IkappaB (IκB). These results indicated that the anti-inflammatory effects of these benzaldehyde derivatives in LPS-stimulated RAW264.7 macrophages were due to the inactivation of the NF-κB pathway. In addition, compounds 1 and 2 induced heme oxygenase-1 (HO-1) expression through the nuclear transcription factor-E2–related factor 2 (Nrf2) translocation. The inhibitory effects of compounds 1 and 2 on the production of pro-inflammatory mediators and on NF-κB binding activity were reversed by HO-1 inhibitor tin protoporphyrin (SnPP). Thus, the anti-inflammatory effects of compounds 1 and 2 also correlated with their ability of inducing HO-1 expression.
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- 2014
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88. Role of the MoYAK1 protein kinase gene in Magnaporthe oryzae development and pathogenicity
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Joon-Hee, Han, Hye-Min, Lee, Jong-Hwan, Shin, Yong-Hwan, Lee, and Kyoung Su, Kim
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Virulence ,Genes, Fungal ,Hyphae ,Oryza ,Spores, Fungal ,Fungal Proteins ,Magnaporthe ,Cell Wall ,Cyclic AMP ,Hydrophobic and Hydrophilic Interactions ,Protein Kinases ,Gene Deletion ,Glycogen ,Plant Diseases - Abstract
Conidiation and appressorium differentiation are key processes for polycyclic dissemination and infection in many pathogens. Our previous study using DNA microarray led to the discovery of the MoYAK1 gene in Magnaporthe oryzae that is orthologous to YAK1 in Saccharomyces cerevisiae. Although the mechanistic roles of YAK1 in S. cerevisiae have been described, roles of MoYAK1 in M. oryzae, a phytopathogenic fungus responsible for rice blast, remain uncharacterized. Targeted disruption of MoYAK1 results in pleiotropic defects in M. oryzae development and pathogenicity. The ΔMoyak1 mutant exhibits a severe reduction in aerial hyphal formation and conidiation. Conidia in the ΔMoyak1 are delayed in germination and demonstrate decreased glycogen content in a conidial age-dependent manner. The expression of hydrophobin-coding genes is dramatically changed in the ΔMoyak1 mutant, leading to a loss of surface hydrophobicity. Unlike the complete inability of the ΔMoyak1 mutant to develop appressoria on an inductive surface, the mutant forms appressoria of abnormal morphology in response to exogenous cyclic adenosine-5'-monophosphate and host-driven signals, which are all defective in penetrating host tissues due to abnormalities in glycogen and lipid metabolism, turgor generation and cell wall integrity. These data indicate that MoYAK1 is a protein kinase important for the development and pathogenicity of M. oryzae.
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- 2014
89. Anti-neuroinflammatory effect of aurantiamide acetate from the marine fungus Aspergillus sp. SF-5921: inhibition of NF-κB and MAPK pathways in lipopolysaccharide-induced mouse BV2 microglial cells
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Chi-Su Yoon, Dong-Sung Lee, Hyuncheol Oh, Kyoung Su Kim, Wonmin Ko, Jae Hak Sohn, Dong-Cheol Kim, Youn-Chul Kim, and Joung Han Yim
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MAPK/ERK pathway ,Lipopolysaccharide ,Cell Survival ,MAP Kinase Signaling System ,p38 mitogen-activated protein kinases ,Immunology ,Blotting, Western ,Interleukin-1beta ,Anti-Inflammatory Agents ,Biology ,Nitric Oxide ,Dinoprostone ,Nitric oxide ,Cell Line ,chemistry.chemical_compound ,Mice ,Immunology and Allergy ,Animals ,Pharmacology ,Molecular Structure ,Kinase ,Tumor Necrosis Factor-alpha ,NF-kappa B ,NF-κB ,Dipeptides ,Molecular biology ,Porifera ,Aspergillus ,chemistry ,Biochemistry ,Phosphorylation ,Tumor necrosis factor alpha ,Microglia - Abstract
In the course of a search for anti-neuroinflammatory metabolites from marine fungi, aurantiamide acetate (1) was isolated from marine-derived Aspergillus sp. as an anti-neuroinflammatory component. Compound 1 dose-dependently inhibited the production of nitric oxide (NO) and prostaglandin E2 (PGE2) in BV2 microglial cells. It also attenuated inducible NO synthase (iNOS), cyclooxygenase-2 (COX-2), and other pro-inflammatory cytokines, such as interleukin-1β (IL-1β) and tumor necrosis factor-α (TNF-α). In a further study designed to elucidate the mechanism of its anti-neuroinflammatory effect, compound 1 was shown to block the activation of nuclear factor-kappa B (NF-κB) in lipopolysaccharide (LPS)-induced BV2 microglial cells by inhibiting the phosphorylation of the inhibitor kappa B-α (IκB)-α. In addition, compound 1 decreased the phosphorylation levels of c-Jun N-terminal kinase (JNK) and p38 mitogen-activated protein kinases (MAPKs). These results suggest that compound 1 has an anti-neuroinflammatory effect on LPS stimulation through its inhibition of the NF-κB, JNK and p38 pathways.
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- 2014
90. A New Record and Characterization of Asparagus Purple Spot Caused by Stemphylium vesicarium in Korea.
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Joon-Hee Han, Jong-Hwan Shin, Teng Fu, and Kyoung Su Kim
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RNA sequencing ,ASPARAGUS ,CYTOCHROME b - Abstract
In 2017, small, elliptical, brownish purple spots on spears and ferns of asparagus were found in fields of Gangwon-do. The isolated fungal species was identified as an ascomycete Stemphylium vesicarium based on morphological characteristics and molecular phylogenic analyses including nucleotide sequences of the internal transcribed spacer (ITS), glyceraldehyde- 3-phosphate dehydrogenase (GAPDH), and cytochrome b (cytb). A pathogenicity test revealed that S. vesicarium was the causal agent of purple spot disease on asparagus. The occurrence of purple spots caused by S. vesicarium on asparagus is the first report in Korea. [ABSTRACT FROM AUTHOR]
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- 2019
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91. Role of MoAND1-mediated nuclear positioning in morphogenesis and pathogenicity in the rice blast fungus, Magnaporthe oryzae
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Yong-Hwan Lee, Kyoung Su Kim, Junhyun Jeon, Seongbeom Kim, and Heekyoung Rho
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Hypha ,Asexual reproduction ,Mutant ,Saccharomyces cerevisiae ,Morphogenesis ,Microbiology ,Aspergillus nidulans ,Conidium ,Fungal Proteins ,MoAND1 ,Genetics ,Pathogenicity ,Plant Diseases ,Appressorium formation ,Cell Nucleus ,Appressorium ,biology ,Sequence Homology, Amino Acid ,fungi ,Oryza ,Spores, Fungal ,biology.organism_classification ,Spore ,Nuclear positioning ,Cytoskeletal Proteins ,Magnaporthe ,Rice blast ,Gene Deletion - Abstract
To cause disease on host plants, many phytopathogenic fungi undergo morphological transitions including development of reproductive structures as well as specialized infection structures called appressoria. Such morphological transitions display distinct nuclear dynamics. Here we report the developmental requirement of MoAND1-mediated nuclear positioning for pathogenesis of the rice blast fungus, Magnaporthe oryzae. The MoAND1 gene encodes a protein that shows high similarity to Num1 in Saccharomyces cerevisiae and ApsA in Aspergillus nidulans, both of which are cell cortex proteins involved in nuclear migration and positioning. Targeted deletion of MoAND1 did not affect radial growth of the fungus but impaired nuclear distribution along the hyphae, which is reminiscent of ApsA mutant. In contrast to the wild-type, which produces three to five spores in a sympodial manner on the conidiophore, only a single spore was borne on the conidiophore of ΔMoand1, resulting in ∼65% decrease in conidia production, compared to the wild-type. The mutant conidia displayed abnormalities in septation pattern and nuclear distribution, which were correlated with their inability to germinate. Spores of the mutant that did germinate were capable of differentiating appressoria but were defective in the execution of programmed nuclear migration and positioning during development. Furthermore, mutant appressoria were not fully functional, leading to delay in penetration of host plants. However, the ability of ΔMoand1 to grow inside host tissues was comparable to that of the wild-type. All these defects greatly decreased the virulence of the mutant. Taken together, our data suggest that there is a stringent but incomplete developmental requirement for proper migration and positioning of fungal nuclei mediated by MoAND1 during asexual reproduction and pre-penetration phase of fungal pathogenesis.
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- 2013
92. Anti-inflammatory effect of neoechinulin a from the marine fungus Eurotium sp. SF-5989 through the suppression of NF-кB and p38 MAPK Pathways in lipopolysaccharide-stimulated RAW264.7 macrophages
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Xiang Cui, Kyoung Su Kim, Joung Han Yim, Jae Hak Sohn, Youn-Chul Kim, Hyuncheol Oh, and Dong-Sung Lee
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MAPK/ERK pathway ,Lipopolysaccharides ,Lipopolysaccharide ,p38 mitogen-activated protein kinases ,Anti-Inflammatory Agents ,Pharmaceutical Science ,p38 Mitogen-Activated Protein Kinases ,Piperazines ,Article ,NF-κB ,Analytical Chemistry ,Nitric oxide ,Cell Line ,Indole Alkaloids ,lcsh:QD241-441 ,chemistry.chemical_compound ,Mice ,lcsh:Organic chemistry ,Eurotium ,Drug Discovery ,Animals ,Viability assay ,Physical and Theoretical Chemistry ,Phosphorylation ,Protein kinase A ,biology ,Macrophages ,neoechinulin A ,Organic Chemistry ,NF-kappa B ,Molecular biology ,MAPK ,Eurotium rubrum ,Nitric oxide synthase ,chemistry ,Biochemistry ,Chemistry (miscellaneous) ,inflammation ,RAW264.7 macrophages ,biology.protein ,Molecular Medicine ,Tumor necrosis factor alpha ,Signal Transduction - Abstract
In the course of a bioassay-guided study of metabolites from the marine fungus Eurotium sp. SF-5989, two diketopiperazine type indole alkaloids, neoechinulins A and B, were isolated. In this study, we investigated the anti-inflammatory effects of neoechinulins A (1) and B (2) on lipopolysaccharide (LPS)-stimulated RAW264.7 macrophages. Neoechinulin A (1) markedly suppressed the production of nitric oxide (NO) and prostaglandin E2 (PGE2) and the expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) in a dose dependent manner ranging from 12.5 µM to 100 µM without affecting the cell viability. On the other hand, neoechinulin B (2) affected the cell viability at 25 µM although the compound displayed similar inhibitory effect of NO production to neoechinulin A (1) at lower doses. Furthermore, neoechinulin A (1) decreased the secretion of pro-inflammatory cytokines, such as tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β). We also confirmed that neoechinulin A (1) blocked the activation of nuclear factor-kappaB (NF-κB) in LPS-stimulated RAW264.7 macrophages by inhibiting the phosphorylation and degradation of inhibitor kappa B (IκB)-α. Moreover, neoechinulin A (1) decreased p38 mitogen-activated protein kinase (MAPK) phosphorylation. Therefore, these data showed that the anti-inflammatory effects of neoechinulin A (1) in LPS-stimulated RAW264.7 macrophages were due to the inhibition of the NF-κB and p38 MAPK pathways, suggesting that neoechinulin A (1) might be a potential therapeutic agent for the treatment of various inflammatory diseases.
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- 2013
93. The neoflavonoid latifolin isolated from MeOH extract of Dalbergia odorifera attenuates inflammatory responses by inhibiting NF-κB activation via Nrf2-mediated heme oxygenase-1 expression
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Dong-Sung, Lee, Kyoung-Su, Kim, Wonmin, Ko, Bin, Li, Samell, Keo, Gil-Saeng, Jeong, Hyuncheol, Oh, and Youn-Chul, Kim
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Inflammation ,NF-E2-Related Factor 2 ,Tumor Necrosis Factor-alpha ,Dalbergia ,Interleukin-1beta ,Anti-Inflammatory Agents ,NF-kappa B ,Membrane Proteins ,Nitric Oxide Synthase Type II ,Dinoprostone ,Mice, Inbred C57BL ,Mice ,NF-KappaB Inhibitor alpha ,Phenols ,Cyclooxygenase 2 ,Macrophages, Peritoneal ,Animals ,I-kappa B Proteins ,Cells, Cultured ,Heme Oxygenase-1 ,Signal Transduction - Abstract
In Korea and China, the heartwood of Dalbergia odorifera T. Chen is an important traditional medicine used to treat blood disorders, ischemia, swelling, and epigastric pain. In this study, we investigated the inhibitory effects of latifolin, a major neoflavonoid component isolated from the MeOH extract of D. odorifera, on the inflammatory reaction of thioglycollate-elicited peritoneal macrophages exposed to lipopolysaccharide, with a particular focus on heme oxygenase-1 (HO-1) expression and nuclear factor-κB (NF-κB) signaling. Latifolin significantly inhibited the protein and mRNA expression of inducible nitric oxide synthase and COX-2, reduced NO, prostaglandins E2, tumor necrosis factor-α, and interleukin-1β production in primary murine peritoneal macrophages exposed to lipopolysaccharide. Latifolin also suppressed inhibitor κB-α levels, NF-κB nuclear translocation, and NF-κB DNA-binding activity. Furthermore, latifolin upregulated HO-1 expression via nuclear transcription factor-E2-related factor 2 (Nrf2) nuclear translocation. In addition, using inhibitor tin protoporphyrin IX (SnPP), an inhibitor of HO-1, it was verified that the inhibitory effects of latifolin on the proinflammatory mediators and NF-κB DNA-binding activity were associated with the HO-1 expression. These results suggested that the latifolin-mediated up-regulation of HO-1 expression played a critical role in anti-inflammatory effects in macrophages. This study therefore identified potent therapeutic effects of latifolin, which warrants further investigation as a potential treatment for inflammatory diseases.
- Published
- 2013
94. Inhibitory effect of 9-hydroxy-6,7-dimethoxydalbergiquinol from Dalbergia odorifera on the NF-κB-related neuroinflammatory response in lipopolysaccharide-stimulated mouse BV2 microglial cells is mediated by heme oxygenase-1
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Samell Keo, Gil-Saeng Jeong, Hyuncheol Oh, Youn-Chul Kim, Bin Li, Kyoung Su Kim, and Dong-Sung Lee
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Lipopolysaccharides ,NF-E2-Related Factor 2 ,Immunology ,Interleukin-1beta ,Anti-Inflammatory Agents ,Anisoles ,Nitric Oxide ,Dinoprostone ,Proinflammatory cytokine ,Nitric oxide ,Cell Line ,chemistry.chemical_compound ,Mice ,Downregulation and upregulation ,Immunology and Allergy ,Animals ,Neuroinflammation ,Pharmacology ,biology ,Tumor Necrosis Factor-alpha ,NF-kappa B ,Membrane Proteins ,NF-κB ,Molecular biology ,Heme oxygenase ,Nitric oxide synthase ,Allyl Compounds ,Neuroprotective Agents ,Biochemistry ,chemistry ,biology.protein ,Tumor necrosis factor alpha ,Microglia ,Heme Oxygenase-1 - Abstract
The heartwood of Dalbergia odorifera T. Chen (Leguminosae) is an important source of traditional Korean and Chinese medicines. 9-Hydroxy-6,7-dimethoxydalbergiquinol (HDDQ), a compound isolated from D. odorifera, has various biological activities. The aim of this study was to determine the efficacy of HDDQ in modulating the regulation of anti-inflammatory activity through the upregulation of heme oxygenase (HO)-1 in BV2 microglia. HDDQ inhibited the protein expression of inducible nitric oxide synthase (iNOS), iNOS-derived nitric oxide (NO), and the production of cyclooxygenase (COX)-2 and COX-2-derived prostaglandin E2 (PGE2) in lipopolysaccharide (LPS)-stimulated mouse BV2 microglia. HDDQ also reduced tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β) production, and suppressed the phosphorylation and degradation of IκB-α and the nuclear translocation of p65 in mouse BV2 microglia in response to LPS. Furthermore, HDDQ upregulated HO-1 expression via nuclear translocation of nuclear factor E2-related factor 2 (Nrf2) in mouse BV2 microglia. Using tin protoporphyrin (SnPP), an HO activity inhibitor, we verified that the inhibitory effects of HDDQ on the proinflammatory mediators NO, PGE2, TNF-α, and IL-1β, and nuclear factor kappa B (NF-κB) DNA-binding activity are associated with the induction of HO-1 expression. Our data suggest that HDDQ has therapeutic potential against neurodegenerative diseases caused by neuroinflammation.
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- 2013
95. PTP1B Inhibitory and Anti-Inflammatory Effects of Secondary Metabolites Isolated from the Marine-Derived Fungus Penicillium sp. JF-55
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Dong-Sung Lee, Jae Hak Sohn, Kyoung Su Kim, Jong Seog Ahn, Myeong-Suk Kang, Jae-Hyuk Jang, Youn-Chul Kim, Hyuncheol Oh, and Wonmin Ko
- Subjects
medicine.drug_class ,Metabolite ,Anti-Inflammatory Agents ,Pharmaceutical Science ,Protein tyrosine phosphatase ,Biology ,Penicillium sp ,Anti-inflammatory ,Article ,chemistry.chemical_compound ,Mice ,Drug Discovery ,medicine ,Animals ,Humans ,marine-derived fungi ,PTP1B inhibitors ,anti-inflammatory effect ,heme oxygenase-1 ,lcsh:QH301-705.5 ,Pharmacology, Toxicology and Pharmaceutics (miscellaneous) ,Regulation of gene expression ,Protein Tyrosine Phosphatase, Non-Receptor Type 1 ,Dose-Response Relationship, Drug ,NF-kappa B ,Penicillium ,biology.organism_classification ,NFKB1 ,Mice, Inbred C57BL ,Insulin receptor ,lcsh:Biology (General) ,Biochemistry ,chemistry ,Gene Expression Regulation ,Chromones ,Pyrones ,biology.protein ,Phosphorylation ,Inflammation Mediators - Abstract
Protein tyrosine phosphatase 1B (PTP1B) plays a major role in the negative regulation of insulin signaling, and is thus considered as an attractive therapeutic target for the treatment of diabetes. Bioassay-guided investigation of the methylethylketone extract of marine-derived fungus Penicillium sp. JF-55 cultures afforded a new PTP1B inhibitory styrylpyrone-type metabolite named penstyrylpyrone (1), and two known metabolites, anhydrofulvic acid (2) and citromycetin (3). Compounds 1 and 2 inhibited PTP1B activity in a dose-dependent manner, and kinetic analyses of PTP1B inhibition suggested that these compounds inhibited PTP1B activity in a competitive manner. In an effort to gain more biological potential of the isolated compounds, the anti-inflammatory effects of compounds 1-3 were also evaluated. Among the tested compounds, only compound 1 inhibited the production of NO and PGE(2), due to the inhibition of the expression of iNOS and COX-2. Penstyrylpyrone (1) also reduced TNF-alpha and IL-1 beta production, and these anti-inflammatory effects were shown to be correlated with the suppression of the phosphorylation and degradation of I kappa B-alpha, NF-kappa B nuclear translocation, and NF-kappa B DNA binding activity. In addition, using inhibitor tin protoporphyrin (SnPP), an inhibitor of HO-1, it was verified that the inhibitory effects of penstyrylpyrone (1) on the pro-inflammatory mediators and NF-kappa B DNA binding activity were associated with the HO-1 expression. Therefore, these results suggest that penstyrylpyrone (1) suppresses PTP1B activity, as well as the production of pro-inflammatory mediators via NF-kappa B pathway, through expression of anti-inflammatory HO-1.
- Published
- 2013
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96. Gene Expression Profiling during Conidiation in the Rice Blast Pathogen Magnaporthe oryzae
- Author
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Kyoung Su Kim and Yong-Hwan Lee
- Subjects
Magnaporthe ,Fungal Physiology ,Mutant ,Plant Pathogens ,Conidiation ,lcsh:Medicine ,Mycology ,Pathogenesis ,Plant Science ,Microbiology ,Fungal Proteins ,Plant Microbiology ,Culture Techniques ,Gene expression ,Reproduction, Asexual ,lcsh:Science ,Gene ,Biology ,Microbial Pathogens ,Oligonucleotide Array Sequence Analysis ,Sequence Deletion ,Genetics ,Regulation of gene expression ,Multidisciplinary ,biology ,lcsh:R ,Fungal genetics ,Microbial Growth and Development ,Botany ,Oryza ,Plant Pathology ,Spores, Fungal ,biology.organism_classification ,Gene expression profiling ,Host-Pathogen Interaction ,lcsh:Q ,Transcriptome ,Research Article - Abstract
Conidiation of phytopathogenic fungi is a key developmental process that plays a central role in their life cycles and in epidemics. However, there is little information on conidiation-induced molecular changes in the rice blast fungus Magnaporthe oryzae. As a first step to understand conidiogenesis in this fungus, we measured genome-wide gene expression profiles during conidiation using a whole genome oligonucleotide microarray. At a two-fold expression difference, approximately 4.42% and 4.08% of genes were upregulated and downregulated, respectively, during conidiation. The differentially expressed genes were functionally categorized by gene ontology (GO) term analysis, which demonstrated that the gene set encoded proteins that function in metabolism, cell wall biosynthesis, transcription, and molecule transport. To define the events of the complicated process of conidiogenesis, another set of microarray experiments was performed using a deletion mutant for MoHOX2, a stage-specific transcriptional regulator essential for conidial formation, which was expressed de novo in a conidiation-specific manner in M. oryzae. Gene expression profiles were compared between the wild-type and the Delta Mohox2 mutant during conidiation. This analysis defined a common gene set that was upregulated in the wild-type and downregulated in the Delta Mohox2 mutant during conidiation; this gene set is expected to include conidiation-related downstream genes of MoHOX2. We identified several hundred genes that are differentially-expressed during conidiation; our results serve as an important resource for understanding the conidiation, a process in M. oryzae, which is critical for disease development.
- Published
- 2012
97. Involvement of Heme Oxygenase-1 Induction in the Cytoprotective and Immunomodulatory Activities of Viola patrinii in Murine Hippocampal and Microglia Cells
- Author
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Youn-Chul Kim, Hyun-Gyu Choi, Bin Li, Gil-Saeng Jeong, Dong-Sung Lee, Ren Bo An, and Kyoung Su Kim
- Subjects
Article Subject ,biology ,Microglia ,business.industry ,Neurotoxicity ,lcsh:Other systems of medicine ,Pharmacology ,medicine.disease_cause ,medicine.disease ,lcsh:RZ201-999 ,Neuroprotection ,Proinflammatory cytokine ,Heme oxygenase ,Nitric oxide synthase ,medicine.anatomical_structure ,Complementary and alternative medicine ,Immunology ,biology.protein ,Medicine ,business ,Neuroinflammation ,Oxidative stress ,Research Article - Abstract
A number of diseases that lead to injury of the central nervous system are caused by oxidative stress and inflammation in the brain. In this study, NNMBS275, consisting of the ethanol extract ofViola patrinii, showed potent antioxidative and anti-inflammatory activity in murine hippocampal HT22 cells and BV2 microglia. NNMBS275 increased cellular resistance to oxidative injury caused by glutamate-induced neurotoxicity and reactive oxygen species generation in HT22 cells. In addition, the anti-inflammatory effects of NNMBS275 were demonstrated by the suppression of proinflammatory mediators, including proinflammatory enzymes (inducible nitric oxide synthase and cyclooxygenase-2) and cytokines (tumor necrosis factor-αand interleukin-1β). Furthermore, we found that the neuroprotective and anti-inflammatory effects of NNMBS275 were linked to the upregulation of nuclear transcription factor-E2-related factor 2-dependent expression of heme oxygenase-1 in HT22 and BV2 cells. These results suggest that NNMBS275 possesses therapeutic potential against neurodegenerative diseases that are induced by oxidative stress and neuroinflammation.
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- 2012
98. The PEX7-Mediated Peroxisomal Import System Is Required for Fungal Development and Pathogenicity in Magnaporthe oryzae
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Sook-Young Park, Kyoung Su Kim, Yong-Hwan Lee, Jaeduk Goh, Junhyun Jeon, and Jongsun Park
- Subjects
Magnaporthe ,Genes, Fungal ,lcsh:Medicine ,Gene Expression ,Receptors, Cytoplasmic and Nuclear ,Mycology ,Pathogenesis ,Microbiology ,Molecular Genetics ,Fungal Proteins ,Plant Microbiology ,Cell Wall ,Molecular Cell Biology ,Genetics ,Peroxisomes ,Gene Regulation ,lcsh:Science ,Biology ,Microbial Pathogens ,Peroxisomal Targeting Signal 2 Receptor ,Appressorium ,Fungal protein ,Multidisciplinary ,biology ,Peroxisomal matrix ,Thiolase ,lcsh:R ,Fatty Acids ,Fungal genetics ,Fungi ,Computational Biology ,Oryza ,Peroxisome ,Spores, Fungal ,biology.organism_classification ,Lipids ,Protein Transport ,Glucose ,Gene Targeting ,lcsh:Q ,Gene Function ,Porosity ,Gene Deletion ,Research Article - Abstract
In eukaryotes, microbodies called peroxisomes play important roles in cellular activities during the life cycle. Previous studies indicate that peroxisomal functions are important for plant infection in many phytopathogenic fungi, but detailed relationships between fungal pathogenicity and peroxisomal function still remain unclear. Here we report the importance of peroxisomal protein import through PTS2 (Peroxisomal Targeting Signal 2) in fungal development and pathogenicity of Magnaporthe oryzae. Using an Agrobacterium tumefaciens-mediated transformation library, a pathogenicity-defective mutant was isolated from M. oryzae and identified as a T-DNA insert in the PTS2 receptor gene, MoPEX7. Gene disruption of MoPEX7 abolished peroxisomal localization of a thiolase (MoTHL1) containing PTS2, supporting its role in the peroxisomal protein import machinery. ΔMopex7 showed significantly reduced mycelial growth on media containing short-chain fatty acids as a sole carbon source. ΔMopex7 produced fewer conidiophores and conidia, but conidial germination was normal. Conidia of ΔMopex7 were able to develop appressoria, but failed to cause disease in plant cells, except after wound inoculation. Appressoria formed by ΔMopex7 showed a defect in turgor generation due to a delay in lipid degradation and increased cell wall porosity during maturation. Taken together, our results suggest that the MoPEX7-mediated peroxisomal matrix protein import system is required for fungal development and pathogenicity M. oryzae.
- Published
- 2011
99. Sauchinone suppresses pro-inflammatory mediators by inducing heme oxygenase-1 in RAW264.7 macrophages
- Author
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Hyun-Gyu Choi, Dong-Sung Lee, Bin Li, Ho Sub Lee, Youn-Chul Kim, Dae-Gil Kang, Kyoung Su Kim, and Gil-Saeng Jeong
- Subjects
MAPK/ERK pathway ,Lipopolysaccharides ,Lipopolysaccharide ,Metalloporphyrins ,medicine.medical_treatment ,Anti-Inflammatory Agents ,Drug Evaluation, Preclinical ,Pharmaceutical Science ,Nitric Oxide Synthase Type II ,Protoporphyrins ,Dioxoles ,Pharmacology ,Nitric Oxide ,Plant Roots ,Nitric oxide ,Cell Line ,chemistry.chemical_compound ,Mice ,Saururaceae ,medicine ,Animals ,Benzopyrans ,Molecular Targeted Therapy ,Enzyme Inhibitors ,Phosphorylation ,Extracellular Signal-Regulated MAP Kinases ,Heme ,Flavonoids ,Inflammation ,biology ,Tumor Necrosis Factor-alpha ,Macrophages ,General Medicine ,Nitric oxide synthase ,Heme oxygenase ,chemistry ,Biochemistry ,Cyclooxygenase 2 ,biology.protein ,Tumor necrosis factor alpha ,Plant Preparations ,Inflammation Mediators ,Heme Oxygenase-1 ,Prostaglandin E ,Phytotherapy ,Signal Transduction - Abstract
Sauchinone, a biologically active lignan isolated from the roots of Saururus chinensis (LOUR.) BAILL. (Saururaceae), is reported to exert a variety of biological activities, such as hepatoprotective, anti-inflammatory actions and inhibitory effects on bone resorption. In this study, we investigated the effect of sauchinone in suppressing cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) expression, leading to a reduction in COX-2-derived prostaglandin E(2) (PGE(2)) and iNOS-derived nitric oxide (NO) production in lipopolysaccharide (LPS) stimulated RAW264.7 macrophages. Present study also demonstrates the effects of sauchinone in inducing heme oxygenase-1 (HO-1) expression and an increase in heme oxygenase (HO) activity in RAW264.7 macrophages. The effects of sauchinone on LPS-induced PGE(2), NO, tumor necrosis factor-α (TNF-α) and interlukine-1β (IL-1β) production were partially reversed by the HO-1 inhibitor Tin protoporphyrin was also seen in this study. In addition, we found that treatment with extracellular signal-regulated kinase (ERK) inhibitor (PD98059) reduced sauchinone-induced HO-1 expression. Sauchinone also increased ERK phosphorylation. These results suggest that sauchinone inhibits pro-inflammatory mediators through expression of anti-inflammatory HO-1 via ERK pathway.
- Published
- 2011
100. Inhibition Effects of Silver Nanoparticles against Powdery Mildews on Cucumber and Pumpkin
- Author
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Sang Woo Kim, Jin Hee Jung, Yun Seok Kim, Kabir Lamsal, Youn Su Lee, and Kyoung Su Kim
- Subjects
Crop yield ,Outbreak ,food and beverages ,Biology ,Microbiology ,Silver nanoparticle ,Inhibition effect ,Horticulture ,Infectious Diseases ,Powdery mildew ,Disease severity ,Germination ,In vivo ,Botany ,Agricultural chemical ,Silver nanoparticles ,Mycelium ,Research Article - Abstract
Powdery mildew is one of the most devastating diseases in cucurbits. Crop yield can decline as the disease severity increases. In this study, we evaluated the effect of silver nanoparticles against powdery mildew under different cultivation conditions in vitro and in vivo . Silver nanoparticles (WA-CV-WA13B) at various concentrations were applied before and after disease outbreak in plants to determine antifungal activities. In the field tests, the application of 100 ppm silver nanoparticles showed the highest inhibition rate for both before and after the outbreak of disease on cucumbers and pumpkins. Also, the application of 100 ppm silver nanoparticles showed maximum inhibition for the growth of fungal hyphae and conidial germination in in vivo tests. Scanning electron microscope results indicated that the silver nanoparticles caused detrimental effects on both mycelial growth and conidial germination.
- Published
- 2010
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