• Archives of Pharmacal Research
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• 제16권1호
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• pp.36-42
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• 1993

To find biologically active components of the higher fungi of Korea, the carpophores of Auricularia polytricha, a well-known edible mushroom, were extracted with 0.14 M NaCl solution. The extract was successively fractionated by adding ammonium sulfate at various concentrations, and the respective precipitates were separated by centrifugation, then dialyzed and freeze-dried. When a does of 60 mg/kg of each was injected i.p. into ICR mice, the fraction which precipitated at 20% ammonium sulfate showed the highest toxicity, killing seven out of seven mice within two days. The fraction obtained at 40% ammonium sulfate showed the second highest toxicity. The two fractions were named auritoxin I and II after the genus name. However, they Nere shown to have nearly identical composition by physicochemical and 6.8% protein. The polysaccharide moiety was found to have 12.3% $\alpha$-linkage and 87.7% $\beta$-linkage and to be a heteromannoglucan consisting of 45.1% glucose, 435 mannose and 11.0% xylose. The protein moiety contained ten amino adids. The molecular weight of the toxin was $1.5\times10^6$ dalton by Sepharose CL-4B gel filtration. The modian lethal doses of auritoxin in mice were 56.4, 157.2 and 454.6 mg/kg by i.p., s.c. and p.o.administrations, respectively. The signs of intrxication were convulsion during the first 30 minutes after the injection, coma or sleeping within an hour, termor, lacrimation, nasal bleeding congestion, and death in 24 hours. Smong the various organs, the spleen was found to be enlarged remarkably. Human platelet aggregation was inhibited by the addition of auritoxin. The activity of malic dehydrogenase in vitro was inhibited by the toxin.

• BMB Reports
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• 제40권5호
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• pp.783-790
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• 2007

Receptor binding plays an important role in determining host specificity of the Bacillus thuringiensis Cry $\delta$-endotoxins. Mutations in domains II and III have suggested the participation of certain residues in receptor recognition and insect specificity. In the present study, we expressed the cloned domain II-III fragment of Cry4Ba and examined its binding characteristics to mosquito-larval midgut proteins. The 43-kDa Cry4Ba-domain II-III protein over-expressed in Escherichia coli as inclusion bodies was only soluble when carbonate buffer, pH 10.0 was supplemented with 4M urea. After renaturation via stepwise dialysis and subsequent purification, the refolded domain II-III protein, which specifically reacts with anti Cry4Ba-domain III monoclonal antibody, predominantly exists as a $\beta$-sheet structure determined by circular dichroism spectroscopy. In vitro binding analysis to both histological midgut tissue sections and brush border membrane proteins prepared from susceptible Aedes aegypti mosquito-larvae revealed that the isolated Cry4Ba-domain II-III protein showed binding functionality comparable to the 65-kDa full-length active toxin. Altogether, the data present the 43-kDa Cry4Ba fragment comprising domains II and III that was produced in isolation was able to retain its receptor-binding characteristics to the target larval midgut proteins.

• Journal of Acupuncture Research
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• 제25권3호
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• pp.53-69
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• 2008

목적 : 이 연구는 Vipera lebetina turanica의 사독약침액(蛇毒藥鍼液)(Snake venom toxin, SVT)이 인간 신경아세포종의 암세포주인 SK-N-SH 세포에서 암세포성장의 억제 및 그 기전에 대하여 살펴보고자 하였다. 방법 : SVT를 처리한 후 SK-N-SH의 성장억제를 관찰하기 위해 CCK-8 assay와 LDH assay를 시행하였고, apoptosis 평가에는 세포형태의 관찰과 DAPI, TUNEL, Annexin V-PI double staining assay 및 cell detachment assay를 시행하였다. 세포자멸사 관련 세포기전을 보기 위하여 세포주기, 세포내 칼슘량, 세포내 활성산소량 및 미토콘드리아의 세포막전위 변화를 측정하였고, DNA fragmentation assay를 시행하였으며, 세포자멸사 조절 단백인 Bax, Bcl-2, caspase-3, -9의 발현 변화 관찰에는 western blot analysis를 시행하였다. 결과 : SK-N-SH 세포에 SVT를 처리한 후, 신경아세포종 세포의 성장, Apoptosis의 유발 및 기전의 영향을 관찰하여 다음과 같은 결과를 얻었다. 1. SVT를 처리한 SK-N-SH 세포 관찰에서 세포독성은 농도의존적으로 증가하는 경향이 있는 반면 암세포성장의 유의한 억제는 $20{\mu}g/m{\ell}$ SVT에 의해서만 나타났다. 2. 세포자멸사 평가에서 SVT를 처리한 SK-N-SH 세포는 세포자멸사의 특징적 형태를 나타내었다. TUNEL assay에서는 세포자멸사 활성세포가 미약하게 나타난 반면 cell detachment assay와 Annexin V-PI double staining에서는 각각 세포박리와 세포자멸사 활성세포의 유의한 증가를 나타내었다. 3. 세포자멸사 관련 세포기전연구에서 SVT를 처리한 SK-N-SH 세포의 세포주기, 세포 내 칼슘양 및 DNA fragmentation에는 유의한 변화가 관찰되지 않은 반면 세포내 활성산소 양은 유의한 증가를 나타내었고, 그에 따른 미토콘드리아 세포막 전위의 유의한 변동이 관찰되었다. 4. SVT를 처리한 SK-N-SH는 세포자멸사 관련 단백 발현에서 Bax에 대해 유의한 증가를 나타내지 않았으나 caspase-3 및 caspase-9의 유의한 증가와 Bcl-2의 유의한 감소를 나타내었다. 결론 : 이상의 결과는 SVT가 세포 내 활성산소를 증가시킴으로써 미토콘드리아의 세포막전위에 변화를 일으켜 인간 신경아세포종 세포주인 SK-N-SH의 세포박리와 유관한 세포자멸사를 유발함으로써 증식억제 효과가 있음을 입증한 것이다.

• Journal of Acupuncture Research
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• 제25권2호
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• pp.41-57
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• 2008

목적 : 이 연구는 Vipera lebetina turanica의 사독약침액(蛇毒藥鍼液)(Snake venom toxin, SVT)이 인간 신경아세포종의 암세포주인 SK-N-MC 세포에서 암세포성장의 억제 및 그 기전에 대하여 살펴보고자 하였다. 방법 : SVT를 처리한 후 SK-N-MC의 성장억제를 관찰하기 위해 CCK-8 assay와 LDH assay를 시행하였고, apoptosis 평가에는 세포형태의 관찰과 DAPI, TUNEL, Annexin V-PI double staining assay 및 cell detachment assay를 시행하였다. 세포자멸사 관련 세포기전을 보기 위하여 세포주기, 세포내 칼슘량, 세포내 활성산소량 및 미토콘드리아의 세포막전위 변화를 측정하였고, DNA fragmentation assay를 시행하였으며, 세포자멸사 조절 단백인 Bax, Bcl-2, caspase-3, -9의 발현 변화 관찰에는 western blot analysis를 시행하였다. 결과 : SK-N-MC 세포에 SVT를 처리한 후, 신경아세포종 세포의 성장, Apoptosis의 유발 및 기전에 영향을 관찰하여 다음과 같은 결과를 얻었다. 1. SVT를 처리한 SK-N-MC 세포 관찰에서 $20{\mu}g/m{\ell}$ SVT 처리가 암세포성장의 유의한 억제를 나타내었다. 세포독성 관찰에서 SVT처리는 처리하지 않은 것에 비하여 증가를 나타내었다. 2. 세포자멸사 평가에서 SVT를 처리한 SK-N-MC 세포는 세포자멸사의 특징적 형태를 나타내었다. TUNEL assay에서는 세포자멸사 활성세포가 미약하게 나타난 반면 cell detachment assay와 Annexin V-PI double staining에서는 각각 세포박리와 세포자멸사 활성세포의 유의한 증가를 나타내었다. 3. 세포자멸사 관련 세포기전연구에서 SVT를 처리한 SK-N-MC 세포의 세포주기, 세포내 칼슘량 및 DNA fragmentation에는 유의한 변화가 관찰되지 않은 반면 세포내 활성산소 양은 유의한 증가를 나타내었고, 그에 따른 미토콘드리아 세포막 전위의 유의한 변동이 관찰되었다. 4. SVT를 처리한 SK-N-MC는 세포자멸사 관련 단백 발현에서 caspase-9에 대해 유의한 증가를 나타내지 않았으나 Bax 및 caspase-3의 유의한 증가와 Bcl-2의 유의한 감소를 나타내었다. 결론 : 이상의 결과는 SVT가 세포내 활성산소를 증가시키므로 미토콘드리아의 세포막전위에 변화를 일으켜 인간 신경아세포종 세포주인 SK-N-MC의 세포박리와 유관한 세포자멸사를 유발하므로 증식억제 효과가 있음을 입증한 것이다.

• 한국축산식품학회지
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• 제37권5호
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• pp.743-751
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• 2017

During slaughtering, animal blood is typically discarded, resulting in water pollution. However, this discarded blood has valuable components, such as immunoglobulin (Ig). Although several studies have been conducted to develop methods for effective recycling of slaughterhouse blood, they have not been commercially utilized in Korea. Here, we extracted an Ig-rich fraction from porcine blood that was then subjected to various in vitro tests, including pathogen growth inhibition, antigenic cross-reactivity, and anti-toxin activity. The porcine immunoglobulin concentrate (PIC) was effectively purified by eliminating other components, such as albumin, and consisted of approximately $63.2{\pm}2.9%$ IgG and $7.2{\pm}0.4%$ IgM on a protein basis. The results showed that it significantly suppressed the growth of pathogenic bacteria, and bound to all tested pathogens, including both gram-positive and gram-negative species, although the degree of activity differed according to strain. The PIC bound to two types of lipopolysaccharide (LPS) obtained from Escherichia coli O111:B4 and Salmonella enterica serotype typhimurium in a concentration-dependent manner. In addition, the PIC restored the proliferation activity of the lymphoblast K-562 cells when co-incubated with pathogenic LPS. These results confirm that the PIC prepared in this study is a potentially valuable functional food material or diet supplement as an alternative to antibiotics that can protect animals from pathogenic bacteria.

• BMB Reports
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• 제34권4호
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• pp.293-298
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• 2001

Tryptic activation of the 130-kDa Bacillus thuringiensis Cry4B $\delta$-endotoxin produced protease-resistant products of ca. 47 kDa and ca. 21 kDa. The 21-kDa fragment was identified as the N-terminal five-helix bundle (${\alpha}1-{\alpha}5$,) which is a potential candidate for membrane insertion and pore formation. In this study, we constructed the recombinant clone over-expressing this putative pore-forming (PPF) fragment as inclusion bodies in Escherichia coli. The partially purified inclusions were composed of a 23-kDa protein, which cross-reacted with Cry4B antibodies, and whose N-terminus was identical to that of the 130-kDa protein. Dissimilar to protoxin inclusions, the PPF inclusions were only soluble when the carbonate buffer, pH 9.0, was supplemented with 6 M urea. After renaturation via a stepwise dialysis, the refolded PPF protein appeared to exist as an oligomer and was structurally stable upon trypsin treatment. Unlike the 130kDa protoxin, the refolded protein was able to release entrapped glucose from liposomes, and showed comparable activity to the full-length activated toxin, although it lacks larvicidal activity These results, therefore, support the notion that the PPF fragment that consists of ${\alpha}1-{\alpha}5$ of the activated Cry4B toxin is involved in membrane pore-formation.

• The Plant Pathology Journal
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• 제20권1호
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• pp.52-57
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• 2004

Sclerotinia sp. (isolate BWC98-105) causes stem blight and root rot in Leghum sp., and is presently being evaluated as a potential mycoherbicide for the control of Trifoliorium repens. Bioassays have shown that Sclerotinia sp. produces phytotoxic substance which is biologically active against T. repens. Two biologically active compounds, designated as compoundsI and II, were produced in vitro from the culture filtrate of BWC98-105 isolate Sclerotium sp. Compounds I and II were purified by means of liquid-liquid extraction and $C_{18}$ open column chromatography (300 ${\times}$ 30 mm, i.d). To determine the purity, the purified compounds were analyzed by RP-HPLC. The analytical RP-HPLC column was a TOSOH ODS-120T (150 ${\times}$ 4.6 mm i.d, Japan), of which the flow rate was set at 0.7 mL/min using the linear gradient solvent system initiated with 15 % methanol to 85 % methanol for 50 min with monitoring at 254 nm. Under these RP-HPLC conditions, compounds I and II eluted at 3.49 and 4.13 min, respectively. Compound II was found to be most potent and host specific. However, compound I had a unique antibiotic activity against phytopathogenic bacteria like bacterial leaf blight (Xanthomonas oryzae) on rice, where it played a less important role in producing toxicity on T. repens. No toxin activity was detected in the water fraction after partitioning with several organic solvents. However, toxin activity was detected in the ethyl acetate and butanol fractions. In the leaf bioassay using compound II, the disease first appeared within 4-5 h as water soaked rot, which subsequently developed into well-defined blight affecting the whole plant.

• 한국미생물·생명공학회지
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• 제16권5호
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• pp.389-392
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• 1988

Escheriachia coli pSL 2-1 clone은 Bacillus sphaericus 1593의 모기살충 유전자를 클로닝한 재조합 DNA이다. 이 클론이 생산하는 살충독소 단백질의 분자량을 SDS-polyacrylamide gel을 이용하여 측정했다. B. sphaericus 1593균이 생산하는 독소결정체를 분리하여 전기영동을 한 결과는 6개의 단백질밴드(43, 58, 64, 100, 113, 130Kd)가 형성되었으나, 독소결정체를 알칼리 pH로 용해하여 전기영동을 하면 2개의 단백질 밴드(43과 64Kd)만이 나타났다. 그러나 대장균 pSL2-1균이 생산하는 독소단백질을 Sephadex G-200으로 정제하여 모기유충에 살충력이 있는 단백질을 전기영동한 결과는 42Kd만이 나타났다. LC50은 2 $\mu\textrm{g}$/$m\ell$이었다. B. sphaericus와 pSL2-1 clone 생산하는 살충단백질은 42Kd 단백질인 것으로 생각된다.

• The Plant Pathology Journal
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• 제39권1호
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• pp.88-107
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• 2023

In the present investigation, bacterial isolates from infected apple trees causing apple canker during winter were studied in the northern Gyeongbuk Province, Korea. The pathogen was identified as Pseudomonas syringae pv. syringae (Pss) through various physiological and biochemical characterization assays such as BIOLOG, gas chromatography of fatty acid methyl esters, and 16S rRNA. Bioassays for the production of phytotoxins were positive for syringopeptin and syringomycin against Bacillus megaterium and Geotrichum candidum, respectively. The polymerase chain reaction (PCR) method enabled the detection of toxin-producing genes, syrB1, and sypB in Pss. The differentiation of strains was performed using LOPAT and GATTa tests. Pss further exhibited ice nucleation activity (INA) at a temperature of -0.7℃, indicating an INA⁺ bacterium. The ice-nucleating temperature was -4.7℃ for a non-treated control (sterilized distilled water), whereas it was -9.6℃ for an INA^- bacterium Escherichia coli TOP10. These methods detected pathogenic strains from apple orchards. Pss might exist in an apple tree during ice injury, and it secretes a toxin that makes leaves yellow and cause canker symptoms. Until now, Korea has not developed antibiotics targeting Pss. Therefore, it is necessary to develop effective disease control to combat Pss in apple orchards. Pathogenicity test on apple leaves and stems showed canker symptoms. The pathogenic bacterium was re-isolated from symptomatic plant tissue and confirmed as original isolates by 16S rRNA. Repetitive element sequence-based PCR and enterobacterial repetitive intergenic consensus PCR primers revealed different genetic profiles within P. syringae pathovars. High antibiotic susceptibility results showed the misreading of mRNA caused by streptomycin and oxytetracycline.

• The Plant Pathology Journal
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• 제22권3호
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• pp.203-210
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• 2006

Fumonisins are a group of mycotoxins produced by a pathogen Fusarium verticillioides in infected maize kernels. Consumption of fumonisin-contaminated maize has been implicated in a number of animal and human illnesses, including esophageal cancer and neural tube defects. Since the initial discovery, chemistry, toxicology, and biology of fumonisins as well as the maize-Fusarium pathosystem have been extensively studied. Furthermore, in the past decade, significant progress has been made in terms of understanding the molecular biology of toxin biosynthetic genes. However, there is a critical gap in our understanding of the regulatory mechanisms involved in fumonisin biosynthesis. Here, we review and discuss our current knowledge about the molecular mechanisms by which fumonisin biosynthesis is regulated in F. verticillioides. In addition, we discuss the impact of maize kernel environment, particularly sugar and lipid molecules, on fumonisin biosynthesis.