• BMB Reports
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• 제32권4호
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• pp.321-325
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• 1999

NAD(P)H-quinone oxidoreductase (EC 1. 6. 99. 2) was purified form S. cerevisiae. The enzyme readily reduced 2,6-dichlorophenolindophenol, a quinonoid redox dye, as well as substituted benzo- and naphthoquinones, and could accept electrons from either NADH or NADPH. The purified NAD(P)H-quinone oxidoreductase turned out to be capable of reducing nitrosoarenes as well as a variety of quinones. A chemical-trapping technique using 4-chloro-1-naphthol was used to show that the N,N-dimethyl-p-benzoquinonediiminium cation was produced in the reduction of 4-nitroso-N,N-dimethylaniline catalyzed by NAD(P)H-quinone oxidoreductase.

• Bulletin of the Korean Chemical Society
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• 제4권3호
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• pp.139-143
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• 1983

${\beta}$-N-Acetyl-D-glucosaminidase B was highly purified with the following sequence of steps; DEAE-cellulose, CM-cellulose, and Sephadex G-200 gel filtration chromatograpies. The specific activity of the purified ${\beta}$ -N-acetyl-D-glucosaminidase B was 2.2 units/mg protein with 12.9 % yield and 196.2 fold purity. The purified ${\beta}$-N-acetyl-D-glucosaminidase B showed single band on polyacrylamide gel electrophoresis. The final preparation of ${\beta}$ -N-acetyl-D-glucosaminidase B was completely free friom arylsulfatase and ${\beta}$-glucuronidase. ${\beta}$ -N-Acetyl-D-glucosaminidase B had pH optimum of 4.5 in 0.5 M sodium citrate buffer. The molecular weight of ${\beta}$-N-acetyl-D-glucosaminidase B was 133,000 by Sephadex G-200 gel filtration. The Km value of ${\beta}$-N-acetyl-D-glucosaminidase B using p-nitrophenyl-N-acetyl-${\beta}$-D-glucosaminide as substrate was 1.0 mM and $V_{max}$ was 0.014 ${\mu}$ mole/min. ${\beta}$-N-Acetyl-D-glucosaminidase B was stable at $55^{circ}C$ for 70 minutes. The crude ${\beta}$ -N-acetyl-D-glucosamiinidase in 70 % ammonium sulfate retained 93 % activity after 7 months storage at -$55^{circ}C$. Bovine serum albumin, sodium chloride, and phosphate activated ${\beta}$ -N-Acetyl-D-glucosaminidase B. N-Acetyl-D-glucosamine, ${\alpha}$-methyl-D-mannoside, and acetate inhibited ${\beta}$ -N-acetyl-D-glucosaminidase B.

• 한국전기전자재료학회논문지
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• 제13권10호
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• pp.812-816
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• 2000

It is very important to understand the correlation of between inter dielectric(ILD) CMP process and various facility factors supplied to equipment to equipment system. In this paper, the correlation between the various facility factors supplied to CMP equipment system and ILD-CMP process was studied. To prevent the partial over-polishing(edge hot-spot) generated in the wafer edge area during polishing, we analyze various facilities supplied at supply system. With facility shortage of D.I water(DIW) pressure, we introduced an adding purified $N_2$(P$N_2$)gas in polishing head cleaning station for increasing a cleaning effect. DIW pressure and P$N_2$gas factors were not related with removal rate, but edge hot-spot of patterned wafer had a serious relation. We estimated two factors (DIW pressure and P$N_2$gas) for the improvement of CMP process. Especially, we obtained a uniform planarity in patterned wafer and prohibited more than 90% wafer edge over-polishing. In this study, we acknowledged that facility factors supplied to equipment system played an important role in ILD-CMP process.

• Applied Biological Chemistry
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• 제46권3호
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• pp.176-182
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• 2003

한국재래간장으로부터 혈전용해효소를 강하게 생산하는 균주를 선발하고 이를 Bacillus subtilis K7로 동정하였다. B. subtilis K7이 생산하는 혈전용해성 protease를 정제하여 분자량을 확인한 결과 21,500 Da이었다. 정제된 효소의 최적반응조건은 $40^{\circ}C$와 pH 9.0이었으며 pH 5.0라서 12.0까지 안정하고 $50^{\circ}C$에서 20분간 열처리한 후에도 50%이상의 효소활성을 가지며 EDTA, CDTA 및 iodoacetat에 실활하는 효소이었다. 이 효소의 fibrin에 대한 Km 값은 $1.8{\times}10^{-2}$ M이었다.

• 한국균학회지
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• 제33권2호
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• pp.69-74
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• 2005

민자주방망이버섯으로부터 분리한 혈전용해효소의 비활성은 22.78 U/mg 이었으며, fibrin를 직접 용해하는 fibrinolytic enzyme 이었다. 15번째까지 N-terminal amino acid 서열 분석 결과, Tyr-Pro-Ser-Pro-Ser-His-Gln-Thr-Ala-Val-Asn-Ala-Ile-Ile-X로 지금까지 발표되지 않은 새로운 효소였다. 분자량은 34 KDa 이고 pH 7.0 부터 pH 9.5의 넓은 영역에서 높은 활성을 나타내는 alkaline protease 였으며, $55^{\circ}C$에서 가장 큰 활성을 보이는 이 효소는 serine protease 저해제인 phenylmethylsulfonyl fluoride를 첨가한 경우 효소의 활성이 전혀 나타나지 않는 것으로 미루어 높은 혈전용해 활성을 갖는 새로운 serine protease로 생각된다. 또한 $Hg^{2+}$의 금속이온을 첨가한 경우에도 효소의 활성은 완전히 사라졌다.

• Journal of Microbiology and Biotechnology
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• 제8권2호
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• pp.111-118
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• 1998

A bacterium producing unique antistaphylococcal substance (ASS) was isolated from soil samples. The isolated strain KUH-001 was identified to belong to Pseudomonas species from the characteristic properties of its fluorescence and cellular 3-hydroxy fatty acid composition, etc. The ASS component was purified by procedures employing activated carbon adsorption, column chromatography with silica gel, preparative TLC and HPLC. This compound could also be purified mainly by repeating of trituration and precipitation with chilled ether. Purified ASS with a m.p. value of $140~142^{\circ}C$ showed marked stability at high temperature (at $121^{\circ}C$ for 10 min) and extreme pHs (in 1N HC1 and 1N NaOH for 1 day) without significant loss of antibiotic activity. From spectral data of UV, IR, NMR, and FAB-MS, the compound was elucidated as 2-heptyl-4-hydroxyquinoline N-oxide (HHQO). Under the conditions employed, HHQO exhibited a narrow antimicrobial spectrum. active particularly against Staphylococcus aureus including the methicillin resistant strain. Moreover, it did not induce resistance, and besides, interacted synergistically with certain antibiotics such as vancomycin or erythromycin.

• BMB Reports
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• 제28권6호
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• pp.477-483
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• 1995

The recombinant human interferon alpha 2a ($rhIFN-{\alpha}2a$), expressed in Saccharomyces cerevtsiae, was purified from insoluble aggregates. The inclusion body of $rhIFN-{\alpha}$ was solubilized by guanidine salt in the presence of disulfide reducing agent. The refolding of denatured $rhIFN-{\alpha}2a$ was achieved by simple dilution. The authentic interferon alpha, which has two correctly matched disulfide bonds, was seperated from incompletely oxidized $IFN-{\alpha}$ and dimeric $IFN-{\alpha}$ by use of a CM-Sepharose column, followed by size exclusion columns at two different pH conditions. The purified protein has been subjected to detailed physicochemical characterization including sequence determination. Unlike other $rhIFN-{\alpha}2a$ from E. coli reported, the $rhIFN-{\alpha}2a$ from S. cerevisiae has no methionine residue at its N-terminus originating from the start codon, ATG. The pI of the protein was determined to be 6.05 with a single band in the pI gel, which demonstrated that the purified $rhIFN-{\alpha}$ was homogeneous. The structural study using circular dichroism showed that the protein retains its three dimensional structure in the wide range of pH conditions between pH 3 and 9, and only minor strucural deformation was observed at pH 1.0.

• 한국균학회지
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• 제31권3호
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• pp.168-174
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• 2003

C. militaris 균사를 콜로이달 키틴이 첨가된 액체 배지에서 배양한 후 황산암모늄 분별침전, 이온 교환 및 겔 여과 크로마토그래피를 이용하여 배양액 중의 chitianse를 분리 정제하였다. 이 효소의 최적 pH와 온도는 각각 5.5와 $35^{\circ}C$이었으며 겉보기 분자량은 48.5 kDa이었고, 그 Km 값은 0.57 mM이었다. 이 효소는 $Cu^{2+},\;Mn^{2+},\;Hg^{2+},\;Zn^{2+},\;CO_{3}^{2-},\;SO_4^{2-},\;CN^-$ 및 OCN^-$ 이온에 의하여 활성이 억제되었으나, $Mg^{2+}$ 및 $K^+$ 이온에 의하여 활성이 약간 증가되었다. 또한 효소 단백질의 아미노산 잔기와 선택적으로 반응하는 무수말레인산, 무수아세트산 및 N-bromo succinimide에 의하여 84.0% 활성이 억제되어 카르복실기를 가진 아미노산 잔기가 이 효소의 활성 부위에 중요한 역할을 함을 알았다. NAG6에 의한 기질 분해 특이성 실험을 통하여 이 효소는 endo-형태의 chitinase임을 알았다.

• Journal of Applied Biological Chemistry
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• 제58권2호
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• pp.97-100
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• 2015

The thermostable pectinase gene TmPec isolated from Thermotoga maritima was introduced into the NdeI site of pRSET-B vector and expressed in its intact form in Escherichia coli BL21. The overexpressed intact form of pectinase (TmPecN protein) was partially purified by heat-denaturation procedure. TmPecN showed the highest activity between 85 and $95^{\circ}C$, and at approximately pH 6.5. Enzyme activity was stably maintained at temperatures below $85^{\circ}C$. In the presence of $Ca^{2+}$, pectinase activity of TmPecN increased to 128.4% of normal level. In contrast, $Ba^{2+}$, $Zn^{2+}$, and $Mn^{2+}$ strongly inhibited TmPecN activity. We conclude that the biochemical properties of the intact form of TmPecN are comparable to those of the recombinant protein TmPec reported previously.

• 생명과학회지
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• 제11권6호
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• pp.561-567
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• 2001

능이버섯[Sarcodon aspratus(Berk.)S.Ito]의 fibrin 분해 활성물질을 분리정제하기 위하여(N $H_4$)$_2$S $O_4$침전법, DE52 anion exchange column chromatography, Sephacryl-S2000 gel filtration chromatography 및 Mono S cation FPLC를 행하였으며 정제된 효소의 특성을 측정하였다. 혈전용해 요소의 활성물질은 DE52 anion exchange colum chroma-tography에 NaCI의 농도가 0.2M 정도에서 용출되었으며 계속된 Sephacryl-S200 gel fitration chromatography 및 Mono S cation EPLC를 실시한 결과 단일 Peak를 얻었고 혈전용해효소의 특이활성은 55.2 U/mg protein으로 조효소액으로 비하여 11.3 배 증가하였으며 수율은 49.5%이었다. 또한 Mono S cation EPLC에서 얻은 활성획분을 12% SDS-PAGE로 전기영동한 결과 단일 band를 얻었으며 gel filtration의 결과와 비교함으로서 정제된 능이의 혈전용해 효소의 분자량은 29.300 Da인 것으로 확인되었다. 능이로 부터 정제한 혈전용해효소는 pH가 높아질수록 효소활성이 증가하였으며 pH 10.5의 알카리성에서도 안정하였으며 6$0^{\circ}C$이상의 온도에서는 효소활성이 급격히 실활하기 시작하였지만 8$0^{\circ}C$에서 25%의 상대활성을 보였다. 또한 본 효소는 C $u^{2+}$이온 $Co^{3+}$ 이온 등 중금속에 의하여 68%및 38%활성이 저해되었으며 $Ca^{2+}$이온 또는 $Mg^{2+}$의 초딤색 인 EDTA및 serine protease inhibitor이 PMSF에 의하여 활성이 저해되었었다. 이러한 결과들은 능이의 혈전용해효소가 Ca.sup 2+/또는M $g^{2+}$에 의하여 활성이 증가하는 serine protease임을 암시해 주고 있다.