• Journal of Genetic Medicine
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• 제1권1호
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• pp.17-22
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• 1997

The angiotensin converting enzyme (ACE) is a key component of the renin-angiotensin system thought to be important in the pathogenesis of hypertension and cardiovascular diseases. Deletion polymorphism in the ACE gene may be a risk factor for myocardial infarction. The insertion/deletion (I/D) polymorphism of the ACE detected by PCR analysis appears to be associated with hypertension in Koreans and its nucleotide was subcloned into T-vector and its nucleotide sequences were determined. We also examined an association between hypertension and genetic variance of ACE. We identified the angiotensin I-converting enzyme genotype in 127 hypertensive and 189 normotensive Korean subjects. The distribution of ACE genotype II, ID, DD were 39.2%, 40.2%, 20.6% respectively and the frequency for ACE alleles I and D were 0.593 and 0.407, respectively in all subjects. The frequency of D allele in Korean males is higher than that of Korean females (male; 0.438 : female; 0.267), and the frequency of I allele in Korean females is higher than that of Korean males (female; 0.733 : male; 0.562). Genotype distributions of angiotensin I-converting enzyme genes in Korean normal adult population were different from that of Caucasians (P<0.001). There were no significant differences in genotype frequency between the hypertensive control group (n=127) and the normotensive group (n=189). We observed significant differences of ACE genotype distribution between the male group and the female group in total (P=0.001) and in hypertensive Korean subjects (P=0.013).

• Asian-Australasian Journal of Animal Sciences
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• 제19권5호
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• pp.684-689
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• 2006

The present study examined the effects of Tween 80 on the attachment and hydrolytic activity of a cellulase enzyme against ball-milled cellulose (BMC), using the whole component (native CBH I) and the catalysis module (core CBH I) of carbohydrolase I purified from Trichoderma viride (Meicelase, Meiji Seika, Tokyo, Japan). The effects were evaluated as protein concentrations in the supernatant after mixing enzyme and substrate with Tween 80 at room temperature. Tween 80 decreased the adsorption of native CBH I and core CBH I onto BMC (p<0.001) and increased the amount of reducing sugars released from BMC by native CBH I (p<0.001). However, Tween 80 did not enhance the hydrolytic activity of core CBH I. Observations using SEM revealed that Tween 80 caused cellulose filter paper to swell and enhanced surface cracks and filaments caused by native CBH I but not by core CBH I. These results suggested that Tween 80 decreases enzyme adsorption to its substrate but enhances enzymatic activity.

• Natural Product Sciences
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• 제18권3호
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• pp.141-146
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• 2012

Veronica peregrina (Scrophylariaceae) has been widely used as a Korean traditional medicine for the treatment of various pathological conditions including infection, hemorrhage and gastric ulcer. In the current study, we investigated the inhibitory effect of methanolic extracts of V. Peregrina (VPM) on the LPS-mediated nitric oxide (NO) production in mouse (C57BL/6) peritoneal macrophages. NO production was significantly down-regulated by the treatment of VPM dose dependently. To evaluate the mechanism of the inhibitory action of VPM on NO production, we performed iNOS enzyme activity assay and checked the change of inducible nitric oxide synthase (iNOS) levels by Western blotting. Although VPM did not affect iNOS enzyme activity, iNOS protein expression was attenuated by VPM indicating VPM inhibits NO production via suppression of iNOS enzyme expression. In addition, VPM attenuated the expression of another pro-inflammatory mediator such as cyclooxygenase-2 (COX-2) in a dose dependent manner. We also found that VPM can reduce trypsin-induced paw edema in mice. Based on this study, we suggest that V. peregrina may be beneficial in diseases which related to macrophage-mediated inflammatory disorders.

• 한국미생물생명공학회:학술대회논문집
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• 한국미생물생명공학회 1978년도 추계학술대회
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• pp.206.4-206
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• 1978

By utilizillg whole cell enzyme of the Xantho-monas citri IFO 3835, cephalexin is synthesized directly from 7-amino-deacetoxy cephalosporanic acid (7-ADCA) and phenyl glycine methyl ester (PGM). To date, cephalexin has been manufactu-red by chemical process involving fairly large number of steps to protect the amino group of phenly glycine and carboxyl group of 7-ADCA. However, the enzymatic process involves only a single step with 85％ conversion in 90 minutes. The fermentation variables studied indicate that oxygen transfer is limiting step in the enzyme production. Optimum conditions for enzymatic reaction were 37 C, pH 6.0, and the optimum substrate molar ratio of PGM to 7-ADCA was 2. Other variables that are related to the biochemical properties of whole cell enzyme temperature stability, pH stability, kinetic constants, reusing effect, enzyme loading effect were also evaluated.

• 미생물학회지
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• 제39권4호
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• pp.223-229
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• 2003

2,4,6-Trinitrotoluene (TNT)을 분해할 수 있는 Stenotrophomonas sp. OK-5에서 분리한 NAD(P)H-nitroreductase의 특성을 조사하였다. 먼저 ammonium sulfate precipitation, DEAE-sepharose, 그리고 Q-sepharose 등의 일련의 정제 과정을 통하여 NAD(P)H-nitroreductase을 분리정제하였다. 분취기로부터 얻어진 시료로부터 NAD(P)H-nitroreductase의 효소활성을 가지는 3개의 다른 fractions (I, II 및 III)이 탐침되었다. NAD(P)H-nitroreductase의 fractions I, II, 그리고 III의 비활성(specific activity)은 각각 5.06 unit/mg, 4.95 unit/mg, and 4.86 unit/mg이었으며, crude extract와 비교하여 각각 10.5배, 9.8배, 8.9배 이상 농축되었다. 이 실험에서 이들 3개의 fractions 가운데, fraction I이 가장 높은 비활성을 나타내었다. NAD(P)H-nitroreductase (fractions I, II 및 III)의 효소활성에 영향을 미치는 몇 가지 요인을 조사하였다. 모든 NAD(P)H-nitroreductase (fractions I, II 및 III)의 최적 온도는 30$^{\circ}C$이었으며, 최적 pH는 약 7.5이었다. 4Ag^+, Cu_2^+, Hg_2^+$ 등의 금속이온은 약 80%의 효소활성을 저해하였으나, $Mn_2^+ 이나 Ca_2^+$의 첨가 시에는 약 30~40% 정도의 활성이 감소되었다. 그러나 $Fe_3^+$은 이들 효소의 활성을 증진시켰다. SDS-PAGE에 의해 측정된 NAD(P)H-nitroreductase의 fractions I, II 및 III의 분자량은 모두 약 27 kDa임이 확인되었다.

• Journal of Microbiology and Biotechnology
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• 제8권4호
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• pp.318-324
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• 1998

A ${\beta}$-galactosidase with high transgalactosylic activity was purified from a Bacillus species, registered as KFCC10855. The enzyme preparation showed a single protein band corresponding to a molecular mass of 150 kDa on SDS-PAGE and gave a single peak with the estimated molecular mass of 250 kDa on Sephacryl S-300 gel filtration, suggesting that the enzyme is a homodimeric protein. The amino acid and sugar analyses revealed that the enzyme is a glycoprotein, containing 19.2 weight percent of sugar moieties, and is much more abundant in hydrophilic amino acid residues than in hydrophobic residues, the mole ratio being about 2:1. The pI and optimum pH were determined to be 5.0 and 6.0, respectively. Having a temperature optimum at $70^{\circ}C$ for the hydrolysis of lactose, the enzyme showed good thermal stability. The activity of the enzyme preparation was markedly increased by the presence of exogenous Mg (II) and was decreased by the addition of EDTA. Among the metal ions examined, the most severely inhibitory effect was seen with Ag (I) and Hg (II). Further, results of protein modification by various chemical reagents implied that 1 cysteine, 1 histidine, and 2 methionine residues occur in certain critical sites of the enzyme, most likely including the active site. Enzyme kinetic parameters, measured for both hydrolysis and transgalactosylation of lactose, indicated that the enzyme has an excellent catalytic efficiency for formation of the transgalactosylic products in reaction mixtures containing high concentrations of the substrate.

• 대한수의학회지
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• 제28권2호
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• pp.321-325
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• 1988

This experiment was carried out to determine the progesterone concentration of bovine plasma by liquid phase double antibody enzyme immunoassay. The optimum conditions of assay-system, double (first and second) antibody and carrier (normal rabbit serum) were investigated. The optimum dilution rate of first antibody, second antibody and normal rabbit serum was $10{\times}10^3$ to $15{\times}10^3$, 20 and $1{\times}10^3$ times, respectively.

• KSBB Journal
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• 제6권2호
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• pp.157-166
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• 1991

The structural properties of cellulose are significantly changed with the progress of hydrolysis reaction. The effects of changes on such properties of cellulosic substrate as crystallinity, amicessibility of enzyme to the active site of cellulose surface, and particle size on the kinetics of enzymatic hydrolysis have been studied. Among those physical studies, the apparent surface active site of cellulose particle was found to have the most significant effect on the hydrolysis kinetics. Based on the experimental results, the adsorption affinity of enzyme and hydrolysis rate were mainly influenced by the surface roughness of cellulose particle. The extent of accesssible active site may be expressed as the change of particle diameter. The Langmuir isotherm was proposed in terms of enzyme activity to explain the actual action of enzyme protein.

• 한국생물물리학회:학술대회논문집
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• 한국생물물리학회 1998년도 학술발표회
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• pp.12-12
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• 1998

The interaction between the N-terminal domain of enzyme I (EIN) and the histidine-containing phosphocarrier protein HPr of the Escherichia coli phosphoenolpyruvate：sugar phosphotransferase system has been investigated by Isothermal Titration Calorimetry and heteronuclear magnetic resonance spectroscopy.(omitted)

• 미생물학회지
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• 제23권1호
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• pp.13-19
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• 1985

제한효소 Acc I을 정제하고 그 효소적 특성을 연구하였다. 300g(wet weight)의 Acinetobacter calcoaceticus 로부터 얻은 crude extract를 sample로 하여 ammonium sulfate fractionation을 거쳐 Heparin-agarose, DEAE-se-phades, Affi,-gel Blue, phosphoceIIulose, hydroxylapatite의 순서로 chromatography를 수행한 결고 0 .28mg의 AccI 제한효소를 얻었다. 효소의 specific activity는 mg당 $1.1{\times}10^{s}$ unit 이었다. 정제된 Acc [제한효소는 10% SDS-polyacrylamide gel electrophoresis에서 한개의 band로 나타났으며 그 분자량은 45,000~1,000이었다. 이 효소는 $MgCl_2$ 존재하에, pH 8.0에서 11.0사이에서 최대의 활성을 보였다. NaCl은 이 효소의 활성에는 필요하지 않았으나 150mN이상에서는 급격한 효소 활성의 감소가 있었다.