• KSBB Journal
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• v.21 no.2
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• pp.144-150
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• 2006

The exploitation of metagenome, the access to the natural extant of enormous potential resources, is the way for elucidating the functions of organism in environmental communities, for genomic analyses of uncultured microorganism, and also for the recovery of entirely novel natural products from microbial communities. The major breakthrough in metagenomics is opened by the construction of libraries with total DNAs directly isolated from environmental samples and screening of these libraries by activity and sequence-based approaches. Screening with activity-based approach is presumed as a plausible route for finding new catabolic genes under designed conditions without any prior sequence information. The main limitation of these approaches, however, is the very low positive hits in a single round of screening because transcription, translation and appropriate folding are not always possible in E. coli, a typical surrogate host. Thus, to obtain information about these obstacles, we studied the genetic organization of individual URF's(unidentified open reading frame from metagenome sequenced and deposited in GenBank), especially on the expression factors such as codon usage, promoter region and ribosome binding site(rbs), based on DNA sequence analyses using bioinformatics tools. And then we also investigated the above-mentioned properties for 4100 ORFs(Open Reading Frames) of E. coli K-12 generally used as a host cell for the screening of noble genes from metagenome. Finally, we analyzed the differences between the properties of URFs of metagenome and ORFs of E. coli. Information derived from these comparative metagenomic analyses can provide some specific features or environmental blueprint available to screen a novel biocatalyst efficiently.

• Korean Journal of Food Science and Technology
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• v.41 no.4
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• pp.405-412
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• 2009

The purpose of this study was to determine the inhibitory effect of a glycoprotein isolated from Cudrania tricuspidata Bureau (CTB glycoprotein, 75 kDa) on immunoglobulin E (IgE)-induced allergic inflammation in RBL-2H3 cells. This experiment evaluated the production of intracellular reactive oxygen species (ROS), the activities of mitogenactivated protein kinase (MAPK), transcription factor (c-jun), and cyclooxygenase (COX)-2, and histamine release in cells. The results showed that the CTB glycoprotein inhibited histamine release and COX-2 expression induced by IgE in the cells. The CTB glycoprotein also had suppressive effects on the expressions of ERK1/2, p38 MAPK, c-jun, and the production of intracellular ROS in IgE-treated RBL-2H3 cells. The activities of c-jun and COX-2 were collectively blocked by ERK1/2 inhibitor (PD98059) and p38 MAPK inhibitor (SKF86002), respectively. Hence, we speculate that CTB glycoprotein might be a component with potential use in the preparation of health supplements for the prevention of allergic diseases.

• Journal of Embryo Transfer
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• v.32 no.3
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• pp.209-220
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• 2017

The estrogen-mediated effect of mesenchymal stem cells (MSCs) is a highly critical factor for the clinical application of MSCs. However, the present study is conducted on MSCs derived from adult donors, which have different physiological status with steroid hormonal changes. Therefore, we explores the important role of $17{\beta}$-estradiol (E2) in MSCs derived from female and male newborn piglets (NF- and NM-pBMSCs), which are non-sexually matured donors with steroid hormones. The results revealed that in vitro treatment of MSCs with E2 improved cell proliferation, but the rates varied according to the gender of the newborn donors. Following in vitro treatment of newborn MSCs with E2, mRNA levels of Oct3/4 and Sox2 increased in both genders of MSCs and they may be correlated with both estrogen receptor ${\alpha}$ ($ER{\alpha}$) and $ER{\beta}$ in NF-pBMSCs, but NM-pBMSCs were only correlated with $ER{\alpha}$. Moreover, E2-treated NF-pBMSCs decreased in ${\beta}$-galactosidase activity but no influence on NM-pBMSCs. In E2-mediated differentiation capacity, E2 induced an increase in the osteogenic and chondrogenic abilities of both pBMSCs, but adipogenic ability may increased only in NF-pBMSCs. These results demonstrate that E2 could affect both genders of newborn donor-derived MSCs, but the regulatory role of E2 varies depending on gender-dependent characteristics even though the original newborn donors had not been affected by functional steroid hormones.

• Journal of Microbiology and Biotechnology
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• v.18 no.7
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• pp.1308-1316
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• 2008

Propionibacterium acnes is known to playa pivotal role in the pathogenesis of acne vulgaris. CBT-SL5 is one of the antimicrobial peptides from Enterococcus faecalis SL5, and it has shown antimicrobial activity against P. acnes. The aim of this study was to investigate the anti-inflammatory effect of CBT-SL5 on the inflammation induced by P. acnes in cultured human keratinocyes. Cultured human keratinocytes derived from neonatal foreskin were treated with heat-killed P. acnes to induce inflammation, and then various concentrations of CBT-SL5 were added to the P. acnes-treated keratinocytes. The mRNA expression and protein secretion of interleukin (IL)-8, an inflammation marker, was analyzed by real-time reverse transcription polymerase chain reaction and enzyme-linked immunosorbent assay, respectively. We also analyzed the nuclear factor-kappa B (NF-$\kappaB$) p65 translocation by performing immunofluorescent staining. P. acnes treatment up regulated the IL-8 mRNA expression in the keratinocytes, and this was brought about through both toll-like receptor (TLR)2 and TLR4. At the concentrations of 10, 50, and 100 ng/ml, CBT-SL5 significantly down regulated the P. acnes-induced IL-8 mRNA expression and protein production (p<0.05). At 6 hand 12 h of the treatment, CBT-SL5 significantly suppressed the P. acnes-induced IL-8 mRNA expression. Secretion of IL-8 protein was significantly reduced at 24 h. The functional inhibitory activity of CBT-SL5 was shown by CBT-SL5 suppressing the P. acnes-induced NF-$\kappaB$ translocation from the cytoplasm to the nucleus. These results demonstrated that CBT-SL5 suppressed the P. acnes-induced IL-8 expression in keratinocytes. Therefore, CBT-SL5 may be a novel anti-inflammatory treatment for acne.

• Journal of Microbiology and Biotechnology
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• v.30 no.9
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• pp.1412-1419
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• 2020

Human noroviruses (HuNoVs) are a leading cause of gastroenteritis outbreaks worldwide. However, the paucity of appropriate cell culture models for HuNoV replication has prevented developing effective anti-HuNoV therapies. In this study, first, the replication of the virus at various temperatures in different cells was compared, which showed that lowering the culture temperature from 37℃ significantly increased virus replication in Madin-Darby canine kidney (MDCK) cells. Second, the expression levels of autophagy-, immune-, and apoptosis-related genes at 30℃ and 37℃ were compared to explore factors affecting HuNoV replication. HuNoV cultured at 37℃ showed significantly increased autophagy-related genes (ATG5 and ATG7) and immune-related genes (IFNA, IFNB, ISG15, and NFKB) compared to mock. However, the virus cultured at 30℃ showed significantly decreased expression of autophagy-related genes (ATG5 and ATG7), but not significantly different major immune-related genes (IFNA, ISG15, and NFKB) compared to mock. Importantly, expression of the transcription factor FOXO1, which controls autophagy- and immune-related gene expression, was significantly lower at 30℃. Moreover, FOXO1 inhibition in temperature-optimized MDCK cells enhanced HuNoV replication, highlighting FOXO1 inhibition as an approach for successful virus replication. In the temperature-optimized cells, various HuNoV genotypes were successfully replicated, with GI.8 showing the highest replication levels followed by GII.1, GII.3, and GII.4. Furthermore, ultrastructural analysis of the infected cells revealed functional HuNoV replication at low temperature, with increased cellular apoptosis and decreased autophagic vacuoles. In conclusion, temperature-optimized MDCK cells can be used as a convenient culture model for HuNoV replication by inhibiting FOXO1 and providing adaptability to different genotypes.

• Korean Journal of Environmental Biology
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• v.27 no.1
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• pp.58-65
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• 2009

The chemopreventive effects of naringenin derived from citrus on tumor migration and the possible mechanisms involved in this protection were investigated in HT-1080 tumor cells. In this study, we found that naringenin reduced phorbol 12-myristate 13-acetate (PMA)-enhanced matrix metalloproteinases (MMP)-9 activation in a dose-dependant manner and further inhibited HT-1080 cell migration. In addition, naringenin suppressed PMA-enhanced expression of MMP-9 protein, mRNA and transcription activity levels through suppression of nuclear factor $\kappa$B (NF-$\kappa$B) activation and activator protein-1 (AP-1) translocation without changing tissue inhibitor of metalloproteinase (TIMP)-1 level. Therefore, our results suggested that the inhibitory effects of naringenin on MMP-9 activation, relation of tumor migration in vitro possibly involve mechanisms related to its ability to suppress PMA-enhanced MMP-9 gene and protein expression through NF-$\kappa$B activation and AP-1 translocation. Overall, naringenin may be a valuable anti-invasive drug candidate for cancer therapy.

• Proceedings of the Korean Society of Toxicology Conference
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• 2002.11b
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• pp.14-40
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• 2002

15-Deoxy- Δ$\^$12,14/-prostaglandin J$_2$ (15-deoxy-PGJ$_2$), a naturally occurring ligand activates the peroxisome proliferator-activated receptor-${\gamma}$ (PPAR-${\gamma}$). Activation of PPAR-y has been found to induce cell differentiation such as adipose cell and macrophage. Here it was investigated whether 15-deoxy-PGJ$_2$ has neuronal cell differentiation and possible underlying molecular mechanisms. Dopaminergic differentiating PC 12 cells treated with 15-deoxy-PGJ$_2$ (0.2 to 1.6 ${\mu}$M) alone showed measurable neurite extension and expression of neurofilament, markers of cell differentiation. However much greater extent of neurite extension and expression of neurofilament was observed in the presence of NGF (50 ng/$m\ell$). In parallel with its increasing effect on the neurite extension and expression of neurofilament, 15-deoxy-PGJ$_2$ enhanced NGF-induced p38 MAP kinase expression and its phosphorylation in addition to the activation of transcription factor AP-1 in a dose dependent manner. Moreover, pretreatment of SD 203580, a specific inhibitor of p38 MAP kinase inhibited the promoting effect of 15-deoxy-PGJ$_2$ (0.8 ${\mu}$M) on NGF-induced neurite extension. This inhibition correlated well with the ability of SB203580 to inhibit the enhancing effect of 15-deoxy-PGJ$_2$ on the expression of p38 MAP kinase and activation of AP-1. The promoting ability of 15-deoxy-PGJ$_2$ did not occur through PPAR-${\gamma}$, as synthetic PPAR-${\gamma}$ agonist and antagonist did not change the neurite promoting effect of 15-deoxy-PGJ$_2$. In addition, contrast to other cells (embryonic midbrain and SK-N-MC cells), PPAR-${\gamma}$ was not expressed in PC-12 cells. Other structure related prostaglandins, PGD$_2$ and PGE$_2$ acting via a cell surface G-protein-coupled receptor (GPCR) did not increase basal or NGF-induced neurite extension. Moreover, GPCR (EP and DP receptor) antagonists did not alter the promoting effect of 15-deoxy-PGJ$_2$ on neurite extension and activation of p38 MAP kinase, suggesting that the promoting effect of 15-deoxy-PGJ$_2$ may not be mediated GPCR. These data demonstrate that activation of p38 MAP kinase in conjunction with AP-1 signal pathway may be important in the promoting activity of 15-deoxy-PGJ$_2$ on the differentiation of PC12 cells.

• Biomolecules & Therapeutics
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• v.19 no.4
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• pp.431-437
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• 2011

Aberrant activation of microglia has been reported to cause neuronal damages by releasing a variety of pro-inflammatory cytokines. Besides where microglia become active, damages have been also observed in remote places, which is considered due to the migration of activated microglia. Therefore, an agent that could suppress abnormal activation of microglia and their subsequent migration might be valuable in activated microglia-related brain pathologies. The objective of the present study was to evaluate anti-inflammatory effects of betulinic acid on lipopolysaccharide (LPS)-stimulated BV2 microglial cells. Pretreatment of betulinic acid significantly attenuated LPS-induced NO production and protein expression of iNOS. Betulinic acid also significantly suppressed LPS-induced release and expression of cytokines such as TNF-${\alpha}$ and IL-$1{\beta}$. Furthermore, betulinic acid significantly uppressed LPS-induced MMP-9 expression, which has been suggested to play an important role in the migration of activated microglia. In order to understand the possible mechanism by which betulinic acid suppresses LPS-induced cytokine production and migration of microglia, the role of NF-kB, a major pro-inflammatory transcription factor, was examined. Betulinic acid significantly suppressed LPS-induced degradation of IKB, which retains NF-kB in the cytoplasm. Therefore, nuclear translocation of NF-kB upon LPS stimulation was significantly suppressed with betulinic acid. Taken together, the present study for the first time demonstrates that betulinic acid possesses anti-inflammatory activity through the suppression of nuclear translocation of NF-kB in BV2 microglial cells.

• Journal of Life Science
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• v.26 no.7
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• pp.868-874
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• 2016

Receptor-interacting protein kinase 1 (RIPK1) and RIPK3 are members of the serine or threonine protein kinase superfamily that phosphorylates the hydroxyl group of serine or threonine through the highly conserved kinase region. The RIPK family plays a crucial role not only in inflammation and innate immunity, but also in mediating programmed cell death, such as apoptosis and necroptosis. The interaction between RIPK1 and other TNFR1-related proteins has been shown to assemble a signaling complex I that controls activation of the pro-survival transcription factor NF-κB upon binding of cytokines to TNF receptor 1 (TNFR1). Moreover, RIPK1 and RIPK3 interact through their RIP homotypic interaction motifs (RHIMs) to mediate programmed necrosis, which has long been considered an accidental and uncontrolled cell death form with morphological characteristics differing from those of apoptosis. Highly conserved sequences of RHIM in RIPK1 and RIPK3 were shown to regulate their binary interaction, leading to assembly of a cytosolic amyloid complex termed the “necrosome”. The necrosome also contains mixed lineage kinase domain-like protein (MLKL), which has been found recently to be a substrate of RIPK3 to mediate downstream signaling. This review provides an overview of the functional and physiological characteristics of RIPKs and MLKL in TNF signaling.

• Journal of Life Science
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• v.22 no.3
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• pp.417-427
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• 2012

We compared the transcriptome in response to propanol stress in wild-type and propanol-resistant mutant Escherichia coli using the DNA microarray technique. The correlation value of RNA expression between the propanol-treated wild type and the untreated-one was about 0.949, and 50 genes were differentially expressed by more than twofold in both samples. The correlation value of RNA expression between the propanol-treated mutant and the untreated one was about 0.951, and 71 genes in two samples showed differential expression patterns. However, the values between the wild type and mutant, regardless of propanol addition, were 0.974-0.992 and only 1-2 genes were differentially expressed in the two strains. The representative characteristics among differentially expressed genes in W3110 or P19 treated with propanol compared to untreated samples were up-regulation of hest shock response genes and down-regulation of genes relating to ribosome biosynthesis. In addition, many genes were regulated by transcription regulation factors such as ArcA, CRP, FNR, H-NS, GatR, or PurR and overexpressed by sigma factor RpoH. We confirmed that RpoH mediated an important host defense function in propanol stress in E. coli W3110 and P19 by comparison of cell growth rate among the wild type, rpoH disruptant mutant, and rpoH-complemented strain.