• Proceedings of the Zoological Society Korea Conference
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• 2000.10a
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• pp.230.3-231
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• 2000

No Abstract, See Full Text

• Proceedings of the Korean Society of Sericultural Science Conference
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• 2005.11a
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• pp.62-62
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• 2005

• Proceedings of the Korean Society of Life Science Conference
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• 2007.10a
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• pp.78.1-78.1
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• 2007

See Full Text

• Journal of Microbiology and Biotechnology
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• v.20 no.6
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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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• v.30 no.5
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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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• v.22 no.1
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• pp.53-57
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• 2007

We have studied biochemical characterization of lectin purified from kidney bean seedling through PBS extraction, $(NH_4)_2SO_4$ precipitation, and Sephadex G-100 affinity chromatography. The lectin was agglutinated by rabbit erythrocytes. This lectin analyzed by SDS-PAGE is a tetramer composed of two subunits with molecular weights of 46 and 44 kDa. The optimal temperature and thermal stability of the lectin was 30$^{\circ}C$ and 40-80$^{\circ}C$, respectively. The maximal pH of this lectin was pH 8.2.

• BMB Reports
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• v.35 no.3
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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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• v.28 no.3
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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.

• Journal of Life Science
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• v.17 no.2 s.82
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• pp.254-259
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• 2007

Biochemical characterization of lectin isolated from fruit of cherry tomato through neutral saline extraction, ammonium sulfate precipitation, and affinity chromatography on Sephadex G-200 was studied. The lectin was agglutinated by trypsin-treated human ABO erythrocytes, and the most pronounced activity of agglutination was observed at B type erythrocyte. The analysis of the lectin by SDS-PAGE showed the high intensity band with molecular weights of 10.7 kDa. The optimal temperature and thermal stability of the lectin was $40^{\circ}C$ and $40-60^{\circ}C$, respectively. The maximal pH of this lectin was pH 7.2.

• Journal of Life Science
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• v.16 no.2 s.75
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• pp.297-301
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• 2006

For developing natural antibacterial agents from Houttuynia cordata Thunb., antibacterial effects of volatile flavor component using various bacterial sp. were tested. Extraction from Houttuynia cordata Thunb. by using SDE (Simultaneous steam Distillation-Extraction) showed strong antibacterial activities against Vibrio and Bacillus genus, such as Vibrio. cholerae, V. parahaemolyticus, V. vulnificus, Bacillus. cereus, and B. subtilis. Then chemical compositions of leaf and stem were analyzed. The contents of crude protein, lipid, and ash in stem were less than those of leaf, but fiber contents were higher than those of leaf. Among the amino acids, aspartic acid, glutamic acid, glycine, and arginine were higher than those of other amino acids. Linolenic acid, linoleic acid, oleic acid, and palmitic acid were major fatty acids. Major minerals of Houttuynia cordata Thunb. were potassium, calcium, phosphorus, magnesium, iron, zinc, and copper. Especially, in the case of potassium, it was highest.