• 생명과학회지
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• 제10권6호
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• pp.621-629
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• 2000

Camptothecin (CPT) is an antitumor alkaloid that has been isolated from the Chinese tree, Camptotheca acuminata. The cytotoxicity of CPT has been correlated to its inhibition of DNA topoisomerase (Topo) I by stabilizing drug-enzyme-DNA “cleavable complex" resulting in DNA single-strand breaks and DNA-protein crosslinks. This studies were designed to elucidate whether CPT regulates Topo I mediated by CPT in DNAs containing c-myc protooncogene. We have conducted experiments on Topo I purification, pUC-MYC I cloning and Topo I assay using electrophoresis, quantitative RT-PCR and Northern blotting techniques. CPT ingibited the relaxation activity of Topo I in pUC19 DNA at various concentrations (1-1000 $\mu$M), while it enhanced the cleavage of Topo I in the pUC-MYC I by forming a cleavable complex at relatively high concentrations (100-1000 $\mu$M). In HL-60 cells treated with CPT, the expression of c-myc gene was decreased over that in the control group with no changes in the expression of Topo I mRNA. Our results suggest that Topo I is the target of CPT cytotoxicity but it does not affect Topo I extression, and the suppression of c-myc mRNA expression by CPT is due to c-myc damage resulted from formation of a cleavable complex with CPT. CPT.

• 한국동물학회지
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• 제22권4호
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• pp.141-152
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• 1979

고양이 백혈병 바이러스에서 reverse transcriptase를 분리하여 생화학적 및 면역학적 연구를 하였다. 분자량은 72,000이고, DNA polymerase와 RNase H의 활성은 0.05-1 mM $M_n^2+$와 50-80 mM KCl에서 가장 좋았다. DNA polymerase와 RNase H는 같은 단백질 분자에 있으며, chymotrypsin 처리로서 RNase H를 쪼개낼 수 있으며, 이 RNase H도 reverse transcriptase의 항체에 의해서 활성이 거의 억제 된다. Reverse transcriptase의 항체 결합위치와 활성을 내는 위치는 다른 것 같다.

• 콘크리트학회논문집
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• 제23권3호
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• pp.331-338
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• 2011

이 연구는 미생물 혹은 생물의 다양한 기능을 이용한 환경의 수복(bioremediation)을 활용한 자연 친화형 수질 정화 시멘트 벽돌로서의 가능성을 검토하고자 하였다. 현재 유용 미생물을 건축 소재에 활용하여 수질을 개선하는 연구들이 제안되어 왔다. 이 연구에서는 이러한 미생물의 수질 정화 능력을 이용하는 것으로서 선행 연구의 낫토균 이외에 된장균, 대구 S환경사업소에서 미생물을 탐색하여 16S rDNA 염기서열 분석법에 의해 동정된 유용 미생물 자원들을 이용하였으며, 이렇게 확보된 수질 정화 능력을 가진 유용 미생물 자원들에 대한 시멘트 벽돌에서의 수질 정화 특성을 검토하였다. 또한 시멘트 벽돌에 미생물을 흡착시키기 위하여 제올라이트를 사용 하였으며, SEM 분석을 통하여 제올라이트에 미생물이 흡착되어 있는 것을 확인 할 수 있었다. 실험 결과 유용 미생물을 이용 하였을 때 우수한 오염물질 제거율이 나타났기 때문에 자연 친화형 건설재료의 유용 미생물 활용이 가능하다고 판단되며, 이 연구에서 소개한 미생물 이외에도 다양한 미생물 자원들을 확보하여 건축 소재에 활용 가능한 수질 개선용 유용 미생물 자원들을 확보할 수 있을 것으로 기대된다.

• 한국수산과학회지
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• 제20권2호
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• pp.136-145
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• 1987

말똥 성게를 인공 수정시킨 후 column chromatography법으로 DNA polymerase $\alpha$를 분리 정제하였다. Sephadex G-200과 SDS polyacryamise gel electophoresis에 의한 DNA Polymerase $\alpha$의 분자량은 약 $137,000\~138,000$이였다. 효소활성의 최적 pH는 7.4였고, 칼슘이온 20mM, 나트륨이온 25mM에서 활성이 높았고, 마그네슘 이온은 10 mM 일 때 활성이 높았다. DNA polymerase $\alpha$는 N-ethylmaleimide, aphidicolin, cytosin $\beta-D-arabinofuranoside$ 5'-triphosphate (ara CTP)와 phosphonoacetic acid체 의하여 활성이크게 저하되었다.

• 생태와환경
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• 제53권3호
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• pp.286-294
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• 2020

깔따구(Diptera: Chironomidae)는 저서성 대형무척추동물로 환경오염 및 수질 모니터링에 이용되는 중요한 지표생물이다. 본 연구에서는 인천 수돗물 정수장에서 발견된 깔따구류의 정밀한 종 동정을 위해 형태적 분류와 미토콘드리아 DNA에서 cytochrome c oxidase subunit I (COI) 유전자의 염기서열을 이용하여 분석하였다. 정수장 6곳의 20개체는 안개무늬날개깔따구(Chironomus kiiensis) 12개체, 노랑털깔따구(Chironomus flaviplumus) 6개체, 등깔따구(Chironomus dorsalis) 1개체, 용산무늬깔따구(Polypedilum yongsanensis) 1개체 등 4종으로 확인되었다. 각 깔따구 종의 형태적 특징은 두부, 하순기절, 대악, 안테나, 발톱의 형태적 특징을 살펴보았다. NCBI Genbank에 등록된 깔따구 17종 21개체의 COI 염기서열을 바탕으로 본 연구에서 조사된 20개체의 계통진화적 분석한 결과 각 4종의 깔따구 COI 염기서열은 등록된 동인 종과 높은 상동성을 보이며 (99~100%) 같은 계통군(clade)으로 나타났다. 이러한 결과는 국내 깔따구의 종 동정을 위한 형태적- 유전적 정보를 통합적으로 제공함으로 담수생태계의 모니터링을 위한 주요한 정보로 활용될 것이다.

• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 1994년도 춘계학술대회 and 제3회 신약개발 연구발표회
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• pp.336-336
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• 1994

In order to develope the in vitro short term screen-ing method for carcinogen, we studied a purification method for thymine glycol in oxidaized DNA. Thymine glycol (5,6-dihydroxy-5, 6-dihydrothymine) is the major stable radiolysis poduct in thymine by chemical oxidants and ionzing radiation and it is a useful biomarker among oxidized DNA adducts, related with carcinogenests. Standard thymine glycol was prepared by oxidation of 〔$^3$H〕 thymine with KMnO$_4$ followed by purification with HPLC-LSC system and it was assayed by TLC and gas chromatography-MSD. 〔$^3$H〕 DMA adducts was isolated from E. coli (wild type ) treated with oxidative agents such as benzo(a)pyrene, adriamycin, aflatoxin B$_1$ and KBrO$_3$. These oxidative agents generated free radicals in cells by oxidative metabolism. As a result, thymine glycol was produced in cultured E. coli by four chemicals. This result shows that this methodology should be useful tool in screening oxidative carcinogen.

• 한국수산과학회지
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• 제49권2호
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• pp.137-145
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• 2016

This study screened the biological activity of an acidified gill extract of the Manila clam Ruditapes philippinarum including antimicrobial, hemolytic, membrane permeabilization, and DNA-binding activity, and purified the antimicrobial material. The acidified gill extract showed potent antimicrobial activity against Bacillus subtilis and Escherichia coli without significant hemolytic activity, but showed no membrane permeabilization or DNA-binding ability. An antimicrobial material was purified from the acidified gill extract using C₁₈ reversed-phase and cation-exchange high-performance liquid chromatography (HPLC). Treatment of the purified material with trypsin completely abolished all of the antibacterial activity against Bacillus subtilis, suggesting that the purified material is a proteinaceous antibiotic. The molecular weight of the purified material was 2571.9 Da, but no primary structural information was obtained due to N-terminal blocking. A future study should confirm the primary structure. Our results suggest that the Manila clam gill contains proteinaceous antibiotics that have a role in first-line defense. This information could be used to better understand the Manila clam innate immune system.

• Bulletin of the Korean Chemical Society
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• 제35권9호
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• pp.2753-2757
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• 2014

INtegrase Interactor 1 protein (INI1/hSNF5) or BRG1-associated factor 47 (BAF47) is a SWI/SNF-related matrix associated actin dependent regulator of chromatin subfamily B member. DNA binding domain of INI1/hSNF5 is cloned into E.coli expression vectors, pET32a and purified as a monomer using size exclusion chromatography. NMR data show that $INI1^{DBD}$ has folded state with high population of ${\alpha}$-helices. By fluorescence-quenching experiments, binding affinities between $INI1^{DBD}$ and two double stranded DNA fragments were determined as $29.9{\pm}2.6{\mu}M$ (GAL4_1) and $258.7{\pm}5.8$ (GAL4_2) ${\mu}M$, respectively. Our data revealed that DNA binding domain of INI1/hSNF5 binds to transcriptional DNA sequences, and it could play an important role as a transcriptional regulator.

• 대한수의학회지
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• 제34권2호
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• pp.387-394
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• 1994

To make the genomic DNA probe of Theileria sergenti, the merozoites were purified from bovine erythrocytes. The infected erythrocytes were lysed by Aeromonas hydrophila(Ah-1) hemolysin, and the parasites were isolated by ultracentrifugation on a Percoll discontinuous density gradient. For construction of a T sergenti genomic DNA library, T sergenti DNA was digested with Pstl and the fragments were ligated into the PstI site of pUC19 before transformation of Escherichia coli JM83. Out of thousands of transformants obtained by transformation of E coli JM83 with the genomic library, three plasmids were chosen. The sizes of the inserted DNAs were 2.9kb(2.4kb and 0.5kb) in pKTS1, 4.3kb in pKTS2 and 1.5kb in pKTS3, respectively. The DNA fragments used as probe KTS1(2.4kb), KTS2(4.3kb) and KTS3(1.5kb) were labeled digoxigenin-11-dUTP for the Southern hybridization. In Southern hybridization, all of the probes(KTS1, KTS2 and KTS3) reacted specifically to T sergenti DNA, but not to bovine leucocyte DNA. In order to find out the sensitivities of the digoxigenin-11-dUTP-labeled KTS1 and KTS3 as the probes, purified merozoite DNA and bovine DNA (control) were checked by dot blot hybridization with the probes. Both of the probes, KTS1 and KTS3, detected as minimum amount of 975pg of the T sergenti DNA, but not bovine DNA even to 500ng.

• 한국임상수의학회지
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• 제15권1호
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• pp.140-145
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• 1998

The present study was carried out for the rapid and accurate detection of Anaplasma marginale in cattle using Polymerase Chain Reaction. One pair of primer, BAP-2 and AL34S, were designed to amplify a 409 Up fragment of the A marginale membrane surface protein encoding beta($msp{\beta}l$) gene with a hilly sensitive and specific PCR. A marginale isolated from naturally infected calf in Chonbuk area were used to obtain target genomic DNA for PCR. This study showed that a 409 bp of $msp{\beta}l$ gene fragment could be detected as little as 15 fg of purified A marginale genomic DNA. The amplified fragment with PCR was checked for the identification of $msp{\beta}l$ gene by enzyme restriction and sequencing. Also, the target DNA extracted directly from blood were used in the PCR reactions without prior purification to shorten the detection time. The PCR in the present study was considered convenient and rapid method for the detection of A marginale in whole blood of infected cattle.