• 한국동물학회:학술대회논문집
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• 한국동물학회 2000년도 한국생물과학협회 학술발표대회
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• pp.230.3-231
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• 2000

No Abstract, See Full Text

• 한국잠사학회:학술대회논문집
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• 한국잠사학회 2005년도 제48회 추계 학술연구 발표회
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• pp.62-62
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• 2005

• 한국생명과학회:학술대회논문집
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• 한국생명과학회 2007년도 제48회 학술심포지움 및 추계국제학술대회
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• pp.78.1-78.1
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• 2007

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• Journal of Microbiology and Biotechnology
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• 제20권6호
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• pp.968-973
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• 2010

In order to study its biochemical properties, the integrase (IN) protein of feline foamy virus (FFV) was overexpressed in Escherichia coli, purified by two-step chromatography, (Talon column and heparin column), and characterized in biochemical aspects. For the three enzymatic reactions of the 3'-processing, strand transfer, and disintegration activities, the $Mn^{2+}$ ion was essentially required as a cofactor. Interestingly, $Co^{2+}$ and $Zn^{2+}$ ions were found to act as effective cofactors, whereas other transition elements such as $Ni^{2+}$, $Cu^{2+}$, $La^{3+}$, $Y^{3+}$, $Cd^{2+}$, $Li^{1+}$, $Ba^{2+}$, $Sr^{2+}$, and $V^{3+}$ were not. Regarding the substrate specificity, FFV IN has low substrate specificities as it cleaved in a significant level prototype foamy virus (PFV) U5 LTR substrate as well as FFV U5 LTR substrate, whereas PFV IN did not. Finally, the 3'-processing activity was observed in high concentrations of several solvents such as CHAPS, glycerol, Tween 20, and Triton X-100, which are generally used for dissolution of chemicals in inhibitor screening. Therefore, in this first report showing its biochemical properties, FFV IN is proposed to have low specificities on the use of cofactor and substrate for enzymatic reaction as compared with other retroviral INs.

• Journal of Microbiology and Biotechnology
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• 제30권5호
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• pp.777-784
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• 2020

Self-sufficient P450s, due to their fused nature, are the most effective tools for electron transfer to activate C-H bonds. They catalyze the oxygenation of fatty acids at different omega positions. Here, two new, self-sufficient cytochrome P450s, named 'CYP102A15 and CYP102A170,' from polar Bacillus sp. PAMC 25034 and Paenibacillus sp. PAMC 22724,respectively, were cloned and expressed in E. coli. The genes are homologues of CYP102A1 from Bacillus megaterium. They catalyzed the hydroxylation of both saturated and unsaturated fatty acids ranging in length from C₁₂-C₂₀, with a moderately diverse profile compared to other members of the CYP102A subfamily. CYP102A15 exhibited the highest activity toward linoleic acid with K_m 15.3 μM, and CYP102A170 showed higher activity toward myristic acid with Km 17.4 μM. CYP10A170 also hydroxylated the Eicosapentaenoic acid at ω-1 position only. Various kinetic parameters of both monooxygenases were also determined.

• KSBB Journal
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• 제22권1호
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• pp.53-57
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• 2007

강낭콩 유식물로부터 PBS에 의한 추출, $(NH_4)_2SO_4$ 침전, Sepadex G-100 column chromatography에 의해 lectin을 분리한 다음, 이들의 생화학적 특성으로서 분자량, 적혈구 응집반응, 열 안정성, 최적 온도 및 최적 pH를 연구하였다. 이 과정에 토끼 혈액의 적혈구를 이용하여 활성을 측정하였다. 이 lectin의 분자량은 46 kDa와 44 kDa로서, 각각 2개의 subunit를 갖는 tetramer이다. 정제된 이 lectin의 최적 반응 온도는 30$^{\circ}C$이며, $40\sim80^{\circ}C$에서 열 안정성을 보였다. 또한 이 lectin의 최적 pH는 pH 8.2이다.

• BMB Reports
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• 제35권3호
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• pp.255-261
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• 2002

GTP cyclohydrolase I (E.C. 3.5.4.16) is a homodecameric protein that catalyzes the conversion of GTP to 7,8-dihydroneopterin triphosphate (H2NTP), the initial step in the biosynthesis of pteridines. It was proposed that the enzyme complex could be composed of a dimer of two pentamers, or a pentamer of tightly associated dimers; then the active site of the enzyme was located at the interface of three monomers (Nar et al. 1995a, b). Using mutant enzymes that were made by site-directed mutagenesis, we showed that a decamer of GTP cyclohydrolase I should be composed of a pentamer of five dimers, and that the active site is located between dimers, as analyzed by a series of size exclusion chromatography and the reconstitution experiment. We also show that the residues Lys 136, Arg139, and Glu152 are of particular importance for the oligomerization of the enzyme complex from five dimers to a decamer.

• KSBB Journal
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• 제28권3호
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• pp.151-156
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• 2013

${\beta}$-Glucan type oligomers which have angiotensin I converting enzyme (ACE) inhibitory activity were isolated and characterized from Capsosiphon fulvescens. After C. fulvescens was hydrolysis with Alcalase at $50^{\circ}C$, supernatant was harvested and separated with ultrafiltration membrane (MWCO 2 kDa). Oligomers which were less than 2 kDa of molecular weight were harvested for characterization. The nutrient composition of Alcalase hydrolysate was 89.9% carbohydrate, 4.2% protein and 5.9% sulfate. After ultrafiltration, the nutrient composition of oligomers was changed to 99.88% carbohydrate, 0.07% protein and 0.05% sulfate. The carbohydrate composition of oligomer was glucose (97.2%) and mannose (1.5%). The ACE inhibitory activities of Alcalase hydrolysate and oligomer were 72.1% and 82%, respectively. The molecular weight of oligomer was about 1 kDa. The oligomer was analyzed with FT-IR, $^1H$-NMR and methylation. The oligomers were ${\beta}$-1,3-glucans with ${\beta}$-(1,3)-linked glucose units.

• 생명과학회지
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• 제17권2호통권82호
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• pp.254-259
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• 2007

Neutral saline 추출, ammonium sulfate 침전 및 Sephadex G-200을 사용한 affinity chromatography 과정을 통해 방울토마토 열매에서 분리된 lectin의 생화학적 특성을 연구하였다. 트립신을 처리한 사람의 ABO형 적혈구 모두에서 응집반응이 일어났으며, 이 중 B형 적혈구에서 가장 높은 응집반응이 관찰되었다. 전기영동 분석에 의해 분자량 10.7 kDa의 강도가 높은 밴드가 확인되었다. 분리된 lectin의 최적반응온도는 $40^{\circ}C$이며, 40-60$^{\circ}C$ 범위에서 열에 대해 안정하였다. 또한 최적 pH는 7.2로 조사되었다.

• 생명과학회지
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• 제16권2호
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• pp.297-301
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• 2006

SDE연속추출장치로 추출, 농축한 어성초 휘발성 향기성분 추출물이 15종의 병원성 세균에 대한 항균활성을 측정한 결과는 다음과 같았다. 어성초의 추출물은 주로 Vibrio와 Bacillus속의 세균들에 대해 강한 항균활성을 나타냈고, S. aureus와 epidermidis, S. dysenteriae, C. xerosis, L. monocytogenes에도 비교적 높은 활성을 나타냈다. 하지만 E. coli, S. typhi, E. cloaceae, Y. enterocolitica와 같은 세균들은 어성초 휘발성 향기성분 농축물에 저항성을 가지는 것으로 나타났다. 어성초의 잎과 줄기에 대한 일반성분 중 수분, 조단백질, 조지방, 조회분은 잎에 많이 함유되어 있고 조섬유는 줄기에 많이 함유되어 있었다. 잎에서 9종의 유리아미노산이 검출되었고, 줄기에서는 8종의 유리아미노산이 총 8.81 mg/l00 g 으로 더욱 많이 검출되었다. 지방산조성을 분석한 결과 잎과 줄기에 linolenic acid (C18:3), linoleic acid (C18:2), palmitic acid (C16:0)이 다량 함유되어 있다. 무기성분 중 잎과 줄기에서 K의 함량이 가장 많았고 Ca, P, Mg, Fe, Zn, Cu의 순으로 많이 함유되어 있었다.