• 한국미생물생명공학회:학술대회논문집
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• 한국미생물생명공학회 1979년도 춘계학술대회
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• pp.113.2-114
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• 1979

$\beta-Galactosidase$ is an enzyme which catalizes hydrolysis of lactose, a natural substrate, to glucose and galctose and transferring some monosac-charide units to active acceptors as sugar or alcohol. The occurence of $\beta-Galactosidase$ is known in various microorganisms, animals and higher plants and has been studied by many investigatigators. Especially, a great deal of articles for the enzyme of E. coli have been presented in genetic control mechanism and induction-repression effects of proteins, On the other hand, in the dairly products industry, it is important to hydrolyes lactosd which is the principal sugar of milk and milk products. During the last few years, the interest in enzymatic hydrolysis of milk lactose has teen increased, because of the lactose intolerence in large groups of the population. Microbial $\beta-Galactosidases$ are considered potentially most suitable for processing milk to hydrolyse lactose and, in recent years, the immobilized enzyme from yeast has been examined. Howev, most of the microbial $\beta-Gal$ actosidase are intracellular enzymes, except a few fungal $\beta-Gala-$ ctosidases, and extracellular $\beta-Galactosidase$ which may be favorable to industrial applieation is not so well investigated. On this studies, a mold producing a potent extracellular $\beta-Galactosidase$ was isolated from soil and identified as an imperfect fungus, Beauveria bassians. In this strain, both extracellular and intracellular $\beta-Galactosidases$ were produced simultaneously and a great increase of the extracellular production was acheved by improving the cultural conditions. The extracellular enzyme was purified more than 1, 000 times by procedures including Phosphocellulose and Sephadex G-200 chromatographies. Several characteristics of the enzymewas clarified with this preparation. The enzyme has a main subunit of molecular weight of 80, 000 which makes an active aggregate. And at neutral pH range, it has optimum pH for activity and stability. The Km value was determined to be 0.45$\times$10$^{-3}$ M for $o-Nitrophenyl-\beta-Galactoside.$ In any event, it is interesting to sttudy the $\beta-Galactosidase$ of B. bassiana for the mechanism of secretion and conformational structure of enzyme.

• 한국가축번식학회지
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• 제16권2호
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• pp.87-102
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• 1992

본 연구는 우 casein을 신속, 정확하게 분석할 수 있는 특수 면역효소분석법을 개발하였다. Biotin이 연결된 casein과 peroxidase-conjugated avidin을 사용하였으며 면역화시킨 닭의 난황으로부터 추출한 항체를 이용하여 분석하였다. Sulfo-N-hydroxy succinimido biotin을 사용하여 casein에 biotin을 연결시키고 microplate에 고정한 뒤 peroxidase-conjugated avidin을 결합시켰다. 생산된 항체는 $\alpha$-와 $\beta$-casein에 특이적이었으며, 유청단백질, IgG, 우혈청 알부민과 교차반응은 면역효소분석법과 Western blot에서 나타나지 않았다. 본 분석법의 민감도는 2ng에서 20$\mu\textrm{g}$이었으며 Standard와 시료의 분석시 뚜렷한 평행곡선이 형성되었다. Intra-assay와 Inter-assay의 변이계수는 각각 5.5와 5.7%이었다. 그리고 비유 초기의 casein량을 조사한 결과 분만전 3일경부터 급격히 상승하는 것을 알 수 있었다.

• 대한한방내과학회지
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• 제30권1호
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• pp.9-23
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• 2009

Objectives : Asthma is a chronic inflammatory disorder of the airways by many cells such as mast cells, Th2 lymphocytes and eosinophile. The present study was aimed to evaluate the effects of Salviae miltiorrhizae (SM) on T cell cytokine production, mast cells. and eosinophils, Methods : We screened 13 herbs to find compounds with potential to control Th cytokine production. using concanavalin A (con A)-activated splenocyte cultures. Con A-activated $IFN-\gamma$ and IL-4 levels in supernatants of splenocyte cultures. Bone marrow derived mast cells (BMMC) were incubated with SM and then the expressions of membrane proteins of BMMC were analyzed by fluorescence activated cell sorter (FACS). BALB/c mice sensitized to ovalbumin (OVA) were challenged with aerosolized OVA for 6 weeks. During the last weeks some mice were treated with SM. Then eosinophils in bronchoalveolar lavage fluid (BALf) were counted and pathologic changes of lung tissue were observed with hematoxylin-eosin stain. Results : SM increased $IFN-\gamma$ level on splenocyte culture significantly. but had no significant effects on expressions of ICAM-1, CD62L, integrin $a_4$. c-kit, IL-3 receptors. CD11a, or IgE receptors of BMMC. SM treatment significantly inhibited eosinophil infiltrates in BALf and peribronchial lung inflammation. Conculusions : The present data suggested that SM may have an effect on Th cytokine secretion and eosinophils associated with asthma responses. Therefore SM might be of therapeutic value in treating asthma.

• Biomolecules & Therapeutics
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• 제27권6호
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• pp.530-539
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• 2019

Brain aging is an inevitable process characterized by structural and functional changes and is a major risk factor for neurodegenerative diseases. Most brain aging studies are focused on neurons and less on astrocytes which are the most abundant cells in the brain known to be in charge of various functions including the maintenance of brain physical formation, ion homeostasis, and secretion of various extracellular matrix proteins. Altered mitochondrial dynamics, defective mitophagy or mitochondrial damages are causative factors of mitochondrial dysfunction, which is linked to age-related disorders. Etoposide is an anti-cancer reagent which can induce DNA stress and cellular senescence of cancer cell lines. In this study, we investigated whether etoposide induces senescence and functional alterations in cultured rat astrocytes. Senescence-associated ${\beta}$-galactosidase (SA-${\beta}$-gal) activity was used as a cellular senescence marker. The results indicated that etoposide-treated astrocytes showed cellular senescence phenotypes including increased SA-${\beta}$-gal-positive cells number, increased nuclear size and increased senescence-associated secretory phenotypes (SASP) such as IL-6. We also observed a decreased expression of cell cycle markers, including PhosphoHistone H3/Histone H3 and CDK2, and dysregulation of cellular functions based on wound-healing, neuronal protection, and phagocytosis assays. Finally, mitochondrial dysfunction was noted through the determination of mitochondrial membrane potential using tetramethylrhodamine methyl ester (TMRM) and the measurement of mitochondrial oxygen consumption rate (OCR). These data suggest that etoposide can induce cellular senescence and mitochondrial dysfunction in astrocytes which may have implications in brain aging and neurodegenerative conditions.

• Molecules and Cells
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• 제42권11호
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• pp.755-762
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• 2019

Despite decades of research into colorectal cancer (CRC), there is an ongoing need for treatments that are more effective and safer than those currently available. Lactic acid bacteria (LAB) show beneficial effects in the context of several diseases, including CRC, and are generally regarded as safe. Here, we isolated a Lactobacillus rhamnosus (LR)-derived therapeutic protein, p8, which suppressed CRC proliferation. We found that p8 translocated specifically to the cytosol of DLD-1 cells. Moreover, p8 down-regulated expression of Cyclin B1 and Cdk1, both of which are required for cell cycle progression. We confirmed that p8 exerted strong anti-proliferative activity in a mouse CRC xenograft model. Intraperitoneal injection of recombinant p8 (r-p8) led to a significant reduction (up to 59%) in tumor mass when compared with controls. In recent years, bacterial drug delivery systems (DDSs) have proven to be effective therapeutic agents for acute colitis. Therefore, we aimed to use such systems, particularly LAB, to generate the valuable therapeutic proteins to treat CRC. To this end, we developed a gene expression cassette capable of inducing secretion of large amounts of p8 protein from Pediococcus pentosaceus SL4 (PP). We then confirmed that this protein (PP-p8) exerted anti-proliferative activity in a mouse CRC xenograft model. Oral administration of PP-p8 DDS led to a marked reduction in tumor mass (up to 64%) compared with controls. The PP-p8 DDS using LAB described herein has advantages over other therapeutics; these advantages include improved safety (the protein is a probiotic), cost-free purification, and specific targeting of CRC cells.

• Nutrition Research and Practice
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• 제15권5호
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• pp.591-603
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• 2021

BACKGROUND/OBJECTIVES: Unregulated inflammatory responses caused by hyperglycemia may induce diabetes complications. Hesperetin, a bioflavonoid, is a glycoside in citrus fruits and is known to have antioxidant and anticarcinogenic properties. However, the effect of inflammation on the diabetic environment has not been reported to date. In this study, we investigated the effect of hesperetin on proinflammatory cytokine secretion and its underlying mechanistic regulation in THP-1 macrophages with co-treatment LPS and hyperglycemic conditions. MATERIALS/METHODS: THP-1 cells differentiated by PMA (1 µM) were cultured for 48 h in the presence or absence of hesperetin under normoglycemic (5.5 mM/L glucose) or hyperglycemic (25 mM/L glucose) conditions and then treated with LPS (100 ng/mL) for 6 h before harvesting. Inflammation-related proteins and mRNA levels were evaluated by enzyme-linked immunosorbent assay, western blot, and quantitative polymerase chain reaction analyses. RESULTS: Hesperetin (0-100 µM, 48 h) treatment did not affect cell viability. The tumor necrosis factor-α and interleukin-6 levels increased in cells co-treated with LPS under hyperglycemic conditions compared to normoglycemic conditions, and these increases were decreased by hesperetin treatment. The TLR2/4 and MyD88 activity levels increased in cells co-treated with LPS under hyperglycemic conditions compared to normoglycemic conditions; however, hesperetin treatment inhibited the TLR2/4 and MyD88 activity increases. In addition, nuclear factor-κB (NF-κB) and Acetyl-NF-κB levels increased in response to treatment with LPS under hyperglycemic conditions compared to normoglycemic conditions, but those levels were decreased when treated with hesperetin. SIRT3 and SIRT6 expressions were increased by hesperetin treatment. CONCLUSIONS: Our results suggest that hesperetin may be a potential agent for suppressing inflammation in diabetes.

• Journal of Microbiology and Biotechnology
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• 제29권6호
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• pp.973-983
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• 2019

It is well known that iron is critical for bacterial growth and pathogenic virulence. Due to chemical similarity, $Ga^{3+}$ competes with $Fe^{3+}$ for binding to compounds that usually bind $Fe^{3+}$, thereby interfering with various essential biological reactions. In our present study, gallium(III) nitrate [$Ga(NO_3)_3$] could repress the growth of V. splendidus Vs without complete inhibition. In the presence of $Ga(NO_3)_3$, the secretion of homogentisic acid-melanin (HGA-melanin) in V. splendidus Vs cells could be increased by 4.8-fold, compared to that in the absence of $Ga(NO_3)_3$. HGA-melanin possessed the ability to reduce $Fe^{3+}$ to $Fe^{2+}$. In addition, HGA-melanin increased the mRNA levels of feoA and feoB, genes coding Fe2+ transport system proteins to 1.86- and 6.1-fold, respectively, and promoted bacterial growth to 139.2%. Similarly, the mRNA expression of feoA and feoB was upregulated 4.11-fold and 2.71-fold in the presence of $640{\mu}M$ $Ga(NO_3)_3$, respectively. In conclusion, our study suggested that although $Ga(NO_3)_3$ could interfere with the growth of V. splendidus Vs, it could also stimulate both the production of $Fe^{3+}$-reducing HGA-melanin and the expression of feoA and feoB, which facilitate $Fe^{2+}$ transport in V. splendidus Vs.

• Biomolecules & Therapeutics
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• 제27권3호
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• pp.311-317
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• 2019

Mast cells are the most prominent effector cells of Type 1 hypersensitivity immune responses. CYC116 [4-(2-amino-4-methyl-1,3-thiazol-5-yl)-N-[4-(morpholin-4-yl)phenyl] pyrimidin-2-amine] is under development to be used as an anti-cancer drug, but the inhibitory effects of CYC116 on the activation of mast cells and related allergy diseases have not reported as of yet. In this study, we demonstrated, for the first time, that CYC116 inhibited the degranulation of mast cells by antigen stimulation ($IC_{50}$, ${\sim}1.42{\mu}M$). CYC116 also inhibited the secretion of pro-inflammatory cytokines including TNF-${\alpha}$ ($IC_{50}$, ${\sim}1.10{\mu}M$), and IL-6 ($IC_{50}$, ${\sim}1.24{\mu}M$). CYC116 inhibited the mast cell-mediated allergic responses, passive cutaneous anaphylaxis (ED50, ~22.5 mg/kg), and passive systemic anaphylaxis in a dose-dependent manner in laboratory experiments performed on mice. Specifically, CYC116 inhibited the activity of Fyn in mast cells and inhibited the activation of Syk and Syk-dependent signaling proteins including LAT, $PLC{\gamma}$, Akt, and MAP kinases. Our results suggest that CYC116 could be used as an alternative therapeutic medication for mast cell-mediated allergic disorders, such as atopic dermatitis and allergic rhinitis.

• BMB Reports
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• 제52권2호
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• pp.133-138
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• 2019

Upon viral infection, the 2', 5'-oligoadenylate synthetase (OAS)-ribonuclease L (RNaseL) system works to cleave viral RNA, thereby blocking viral replication. However, it is unclear whether OAS proteins have a role in regulating gene expression. Here, we show that OAS1 and OAS3 act as negative regulators of the expression of chemokines and interferon-responsive genes in human macrophages. Clustered regularly interspaced short palindromic repeats (CRISPR)-CRISPR-associated protein-9 nuclease (Cas9) technology was used to engineer human myeloid cell lines in which the OAS1 or OAS3 gene was deleted. Neither OAS1 nor OAS3 was exclusively responsible for the degradation of rRNA in macrophages stimulated with poly(I:C), a synthetic surrogate for viral double-stranded (ds)RNA. An mRNA sequencing analysis revealed that genes related to type I interferon signaling and chemokine activity were increased in $OAS1^{-/-}$ and $OAS3^{-/-}$ macrophages treated with intracellular poly(I:C). Indeed, retinoic-acid-inducible gene (RIG)-I- and interferon-induced helicase C domain-containing protein (IFIH1 or MDA5)-mediated induction of chemokines and interferon-stimulated genes was regulated by OAS3, but Toll-like receptor 3 (TLR3)- and TLR4-mediated induction of those genes was modulated by OAS1 in macrophages. However, stimulation of these cells with type I interferons had no effect on OAS1- or OAS3-mediated chemokine secretion. These data suggest that OAS1 and OAS3 negatively regulate the expression of chemokines and interferon-responsive genes in human macrophages.

• Journal of Microbiology and Biotechnology
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• 제29권5호
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• pp.820-826
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• 2019

This study evaluated the anti-inflammatory potential of a grasshopper ketone (GK) isolated from the brown alga Sargassum fulvellum on lipopolysaccharide (LPS)-induced RAW 264.7 murine macrophage cell line. GK was isolated and purified from the n-hexane fraction and its structure was verified on the basis of NMR spectroscopic data. GK up to $100{\mu}g/ml$ is not cytotoxic to RAW 264.7, and is an effective inhibitor of LPS-induced NO production in RAW 264.7 cells. The production of pro-inflammatory cytokines, including IL-6, $IL-1{\beta}$, and $TNF-{\alpha}$ was found significantly reduced in $0.1-100{\mu}g/ml$ dose ranges of GK treatment (p < 0.05). We confirmed the dose-dependent and significant inhibition of iNOS and COX-2 proteins expression. In addition, it has been shown that GK induces anti-inflammatory effects by inhibiting MAPKs (ERK, JNK, and p38) and $NF-{\kappa}B$ p65 phosphorylation. Our results show that the anti-inflammatory properties of GK may be due to the inhibition of the $NF-{\kappa}B$ and MAPKs pathways, which are associated with the attenuation of cytokine secretion.