• Molecular & Cellular Toxicology
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• 제1권2호
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• pp.99-105
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• 2005

Perchloroethylene (tetrachloroethylene, PCE), a dry cleaning and degreasing solvent, can enter ground-water through accidental leak or spills. PCE can be degraded to trichloroethylene (TCE), 1, 1-dichloroethylene (DCE) and vinyl chloride (VC) as potential bio-product. These compounds have been reported that they can cause clinical diseases and cytotoxicity. However, only a little genotoxic information of these compounds has been known. In this study, we investigated DNA single strand breaks of PCE, TCE, DCE and VC by single cell gel electrophoresis assay, (comet assay) which is a sensitive, reliable and rapid method for DNA single strand breaks with mouse lymphoma L5178Y cells. From these results, $37.5\;{\mu}g/ml$ of PCE, $189\;{\mu}g/ml$ of TCE and $56.4\;{\mu}g/ml$ of DCE were revealed significant DNA damages in the absence of S-9 metabolic activation system meaning direct-acting mutagen. And in the presence of S-9 metabolic activation system, $41.5\;{\mu}g/ml$ of PCE, $328.7\;{\mu}g/ml$ of TCE and $949\;{\mu}g/ml$ of DCE were induced significant DNA damage. In the case of VC, it was revealed a significant DNA damage in the presence of S-9 metabolic activation system. Therefore, we suggest that chloroethylene compounds (PCE, TCE, DCE and VC) may be induced the DNA damage in a mammalian cell.

• 한방안이비인후피부과학회지
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• 제29권3호
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• pp.95-105
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• 2016

Objectives : Allergic diseases have a various symptoms of hyperresponsiveness and recently hyperresponsive reaction in the chronic phase is reported as the important mechanisms. Cheonggisan(CGS) is used in oriental clinics for curing various skin diseases due to effect of controlling of pruritus. There have been studies on the anti-allergic effect and anti-inflammatory effect of CGS, but there had no study of anti-allergic effects in allergic late inflammation of CGS, so we aimed to find out the effects of CGS in allergic late inflammation in our study.Methods : To investigate the anti-allergy effect and anti-inflammatory effect of CGS, RAW 264.7 macrophage cells and CSG water-extracts were used. Cytotoxic effect of CSG was examined by MTT assay, an oxidative product of NO was measured in the culture medium by the Griess reagent assay. The level of prostaglandin E2(PGE2) was measured by competitive enzyme-linked immunoassay. Cytokine(PGE2, IL-1β, IL-6, TNF-α) was measured by Bio-Plex suspension assay system and quantitative multiplexed cytokine/chemokine assay.Results : We investigated that there was no cytotoxic effect of CGS water-extract at any levels of concentration on RAW 264.7 macrophage cells by MTT assay. CGS water-extracts significantly suppressed the levels of the inflammatory mediators such as NO and PGE2, cytokine of IL-1β, TNF-α at the level of 400 ㎍/㎖ CGS concentration. But there was no significant effect on IL-6 production suppression.Conclusions : These results suggest that CSG water-extract has and anti-inflammatory effects in allergic reaction. These properties may contribute to the allergic diseases and inflammatory related disease care.

• 한국식품과학회지
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• 제52권1호
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• pp.109-112
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• 2020

본 연구에서는 6종의 E. coli 및 S. aureus 유래 박테리오파지 용액에 존재하는 내독소 함량 조사와 파지의 세포독성 여부에 대해 평가하였다. 대표적인 생물학적 내독소 시험법인 LAL assay을 시행하여 9-10 log PFU/mL 농도의 내독소 함량을 확인한 결과, 파지의 임상적용에는 부적합한 수치이나 식품에 존재하는 병원균의 살균 목적의 사용에는 매우 유해하지 않은 수치임을 확인할 수 있었다. 박테리오파지 용액의 세포독성평가를 확인하기 위해 MTT 분석을 시행하여 세포 생존율을 확인하였다. E. coli 파지 용액과 S. aureus 파지 용액 처리군 모두에서 98% 이상의 생존율이 관찰되어 파지용액에 존재하는 내독소 및 파지가 세포독성을 유발하지 않는다는 것을 확인하였다. 그러므로 일반적인 방법으로 증폭, 농축한 파지 용액은 인체에 대한 유해성이 적으며 식품에 살균소독제로 적용하더라도 문제가 없을 것으로 사료된다.

• Journal of Applied Biological Chemistry
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• 제55권1호
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• pp.67-70
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• 2012

Plant MYB transcription factors regulate secondary metabolism, cellular morphogenesis, and plant hormone signaling pathway. MYB proteins in plants consist of two repeats of 50 amino acid residues, which are referred to as R2R3 and they interact with WD40 or basic helix loop helix (bHLH) proteins. Yeast two hybrid assay was determined whether rice MYB protein interacts with either OsTTG1, which contains a WD40 domain, or with OsGL3, which contains a bHLH domain. Among 30 OsMYB proteins, three interacted with OsTTG1 and five interacted with OsGL3. A series of MYB mutants were created to determine the MYB domain important for the interaction with OsTTG1 or OsGL3. By using the yeast two hybrid assay, we found that the R3 motif of OsMYB10 and the R2 motif of OsMYB16 were required for interaction with OsTTG1 and OsGL3 proteins, respectively.

• Genomics & Informatics
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• 제21권2호
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• pp.24.1-24.7
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• 2023

Assays of clinical diagnosis and species identification using molecular markers are performed according to a quantitative method in consideration of sensitivity, cost, speed, convenience, and specificity. However, typical polymerase chain reaction (PCR) assay is difficult to quantify and have various limitations. In addition, to perform quantitative analysis with the quantitative real-time PCR (qRT-PCR) equipment, a standard curve or normalization using reference genes is essential. Within the last a decade, previous studies have reported that the digital PCR (dPCR) assay, a third-generation PCR, can be applied in various fields by overcoming the shortcomings of typical PCR and qRT-PCR assays. We selected Stilla Naica System (Stilla Technologies), Droplet Digital PCR Technology (Bio-Rad), and Lab on an Array Digital Real-Time PCR analyzer system (OPTOLANE) for comparative analysis among the various droplet digital PCR platforms currently in use commercially. Our previous study discovered a molecular marker that can distinguish Hanwoo species (Korean native cattle) using Hanwoo-specific genomic structural variation. Here, we report the pros and cons of the operation of each dPCR platform from various perspectives using this species identification marker. In conclusion, we hope that this study will help researchers to select suitable dPCR platforms according to their purpose and resources.

• Journal of Microbiology and Biotechnology
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• 제21권1호
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• pp.62-70
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• 2011

The antibacterial effects of nine lactic acid bacteria (LAB) against Campylobacter jejuni were investigated by using agar gel diffusion and co-culture assays. Some differences were recorded between the inhibition effects measured with these two methods. Only two LAB, Lb. pentosus CWBI B78 and E. faecium THT, exhibited a clear anti- Campylobacter activity in co-culture assay with dehydrated poultry excreta mixed with ground straw (DPE/GS) as the only growth substrate source. It was observed that the supplementation of such medium with a cellulase A complex (Beldem S.A.) enhanced the antimicrobial effect of both LAB strains. The co-culture medium acidification and the C. jejuni were positively correlated with the cellulase A concentration. The antibacterial effect was characterized by the lactic acid production from the homofermentative E. faecium THT and the lactic and acetic acids production from the heterofermentative Lb. pentosus CWBI B78. The antagonistic properties of LAB strains and enzyme combination could be used in strategies aiming at the reduction of Campylobacter prevalence in the poultry production chain and consequently the risk of human infection.

• Bulletin of the Korean Chemical Society
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• 제29권7호
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• pp.1311-1314
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• 2008

Bacillus halodurans O-methyltransferase (BhOMT) is an S-adenosylmethionine dependent methyltransferase. In our previous study, three dimensional structure of the BhOMT has been determined by comparative homology modeling and automated docking study showed that two hydroxyl groups at 3'- and 4'-position in Bring and structural rigidity of C-ring resulting from the double bond characters between C2 and C3 of flavonoid, were key factors for interaction with BhOMT. In the present study, BhOMT was cloned and expressed. Binding assay was performed on purified BhOMT using fluorescence experiments and binding affinity of luteolin, quercetin, fisetin, and myricetin were measured in the range of $10^7$. Fluorescence quenching experiments indicated that divalent cation plays a critical role on the metal-mediated electrostatic interactions between flavonoid and substrate binding site of BhOMT. Fluorescence study confirmed successfully the data obtained from the docking study and these results imply that hydroxyl group at 7-position of luteolin, quercetin, fisetin, and myricetin forms a stable hydrogen bonding with K211 and carboxyl oxygen of C-ring forms a stable hydrogen bonding with R170. Hydroxyl group at 3'-and 4'-position in the B-ring also has strong $Ca^{2+}$ mediated electrostatic interactions with BhOMT.

• Journal of Microbiology
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• 제42권2호
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• pp.99-102
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• 2004

Bacteriophage PM2 has a closed circular form of double stranded DNA as a genome. This DNA from the phage is a useful source for nick-circle endonuclease assay in the fmol range. Due to difficulties in the maintenance of viral infectivity, storage conditions of the phage should be considered for the puri-fication of PM2 DNA. The proper condition for a short-term storage of less than 2 months is to keep the PM2 phage at 4$^{\circ}C$; whereas the proper condition for a long-term storage of the PM2 phage for over 2 months is to keep it under liquid nitrogen in 7.5 ％ glycerol. The optimal conditions for a high yield of phage progeny were also considered with the goal to achieve a successful PM2 DNA preparation. A MOI(Multiplicity Of Infection) of 0.03, in which the OD$\sub$600/ of the host bacteria was between 0.3 and 0.5, turned out to be optimal for the mass production of PM2 phage with a burst size of about 214. Considerations of PM2 genome size, and the concentrations and radiospecific activities of purified PM2 DNA, are required to measure the endonuclease activity in the fmol range. This study reports the proper quantitation of radioactivity and the yield of purified DNA based on these conditions.

• 대한화학회지
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• 제57권1호
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• pp.81-87
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• 2013

황색포도상구균은 병원에 의한 감염, 혈류 감염을 포함하는 중요한 병원체이다. 특히, 포도상구균의 혈액 수집의 신속한 동정과 메치실린 내성이 일어나게 되면 폐혈증으로 추측되어 진다. 본 저자는 적은 양의 핵산을 등온증폭반응에 적응시켜 증폭산물을 SYBR Green I을 결합하여 염기서열에 특이적으로 검출할 수 있는 새로운 방법을 제시하고 있다. 그리고 이 독특한 유전자 증폭방법은 등온의 상태에서 하나의 효소만으로 증폭이 가능하다. 포도상구균-등온증폭반응은 황색포도상구균에 특이적인 protein A를 암호화하는 spa 유전자와, 메치실린 내성인 pennicillin-binding protein-2를 암호화하는 mecA 유전자를 타겟으로 하여 MRSA와 MRSE를 검출하였다. 본 연구에서는 등온증폭법을 사용하여 황색포도상구균과 표피포도상구균의 임상샘플을 검출하였다. 황색포도상구균과 표피포도상구균을 10배위 정량 희석하여 시리즈별로 샘플을 만들어 실험을 수행하였다. 칩을 기반으로 하는 LAMP법은 포도상구균 감염여부를 쉽고, 빠르고, 정확하게 민감도 있는 검출을 가능하게 해 주었고, 샘플을 측정할 수 있는 한계값을 넘는 상황에 특이적으로 적용할 수 있다.

• Journal of Microbiology
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• 제45권2호
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• pp.153-157
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• 2007

5-enolpyruvylshikimate-3-phosphate synthase (EPSP synthase, EC 2.5.1.19) is the sixth enzyme in the shikimate pathway which is essential for the synthesis of aromatic amino acids and many secondary metabolites. The enzyme is widely involved in glyphosate tolerant transgenic plants because it is the primary target of the nonselective herbicide glyphosate. In this study, the Dunaliella salina EPSP synthase gene was cloned by RT-PCR approach. It contains an open reading frame encoding a protein of 514 amino acids with a calculated molecular weight of 54.6 KDa. The derived amino acid sequence showed high homology with other EPSP synthases. The Dunaliella salina EPSP synthase gene was expressed in Escherichia coli and the recombinant EPSP synthase were identified by functional complementation assay.