• YAKHAK HOEJI
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• v.28 no.3
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• pp.139-147
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• 1984

L-PHA, a lectin having lymphoagglutinating activity but devoid of erythroagglutinability which is contained in Korean white kidney bean (Phaseolus vulgaris L.), was isolated and purified through several techniques such as ion exchange chromatography, hydroxyapatite column and affinity chromatography. Purified L-PHA was identified as a single band by polyacrylamide disc gel electrophoresis. The molecular weight of the L-PHA was estimated about 125, 000 daltons by polyacrylamide gel electrophoresis and it was turned out having one subunit (probably dimer of the Yachnin's model) of Mr~60, 000. Immunochemical studies also tried and these results reconfirmed the purity of this L-PHA.

• Korean Journal of Animal Reproduction
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• v.12 no.1
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• pp.51-62
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• 1988

Spleen cells of mouse immunized with hCG were fused with myeloma cell (SP 2/0 Ag 14) to produce monoclonal antibody against hCG. Several clones of hybridoma secreting monoclonal antibody were established and antibodies were characterized in terms of titer, subisotyping and sensitivity in immunoassay. Several methods, for the purification of anti¬bodies, based on gel-filtration, DEAE-ion exchange chromatography and affinity chromatography. were applied and compared each other by the result of SDS-PAGE. Two-site immunochemiluminometric assay (ICMA) involving the use of an excess concentration of a specific monoclonal antibody passively adsorbed onto the walls of plastic tubes and a chemiluminescence labelled antibody conjugate were de¬veloped for the determination of hCG as a preliminary study.

• Journal of Microbiology and Biotechnology
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• v.25 no.2
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• pp.274-279
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• 2015

Receptor activator of nuclear factor-kappa B ligand (RANKL) is a critical factor in osteoclastogenesis. It makes osteoclasts differentiate and multinucleate in bone remodeling. In the present study, RANKL was expressed as a soluble maltose binding protein (MBP)-fusion protein using the Escherichia coli maltose binding domain tag system (pMAL) expression vector system. The host cell E. coli DH5α was cultured and induced by isopropyl β-_D-1-thiogalactopyranoside for rRANKL expression. Cells were disrupted by sonication to collect soluble MBP-fused rRANKL. The MBP-fusion rRANKL was purified with MBP Trap affinity chromatography and treated with Tobacco Etch Virus nuclear inclusion endopeptidase (TEV protease) to remove the MBP fusion protein. Dialysis was then carried out to remove binding maltose from the cleaved rRANKL solution. The cleaved rRANKL was purified with a second MBP Trap affinity chromatography to separate unsevered MBP-fusion rRANKL and cleaved MBP fusion protein. The purified rRANKL was shown to have biological activity by performing in vitro cell tests. In conclusion, biologically active rRANKL was successfully purified by a simple two-step chromatography purification process with one column.

• The Korean Journal of Mycology
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• v.26 no.4 s.87
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• pp.502-510
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• 1998

The hot-water extract of fruiting bodies in Fomitella fraxinea had potent anti-complementary activities. After fractionation of water-soluble polysaccharides by DEAE-Sephadex A-25 column chromatography, major anti-complementary activity was concentrated into the FF-AP1 among three polysaccharides (FF-NP, FF-AP1, FF-AP2). FF-AP1 was fractionated into $FF-AP1{\alpha}$ and $FF-AP1{\beta}$ obtained from the adsorbed fraction and unadsorbed fraction by affinity chromatography using a ConA-sepharose 4B column, respectively. $FF-AP1{\beta}$, which exihibited the highest anti-complementary activities had an IR absorption peak of $890cm^{-1}$, and a M.W. of about 15,000 (gel filtration). Anti-complementary activity of FF-AP1 decreased greatly by pronase treatment and periodate oxidation. $FF-AP1{\beta}$ responsible for potent anti-complemenary activities of Fomitella fraxinea was an acidic protein-containing heteroglycan consisted of 48% glucose, 13% mannose, and 12% galactose as major component sugars, 9.6% protein, 6% uronic acids.

• Bulletin of the Korean Chemical Society
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• v.28 no.6
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• pp.929-935
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• 2007

The objective of this study was to develop a rapid, simple, and qualitative acetylcholinesterase (AChE)- detection kit, based on a modification of the Ellman and ELISA methods, for the detection of organophosphorus (OP) and carbamate (CB) pesticide. The developed kits were used to screen a large number of agricultural samples (spiked and real) for OP and CB pesticide residues. AChE was extracted from the heads of honeybees (Apis mellifera L.) using Triton X-100, and was purified through 3 steps: diethylaminoethylcellulose chromatography (DEAE), affinity chromatography and membrane filtering, and Mono-Q column chromatography. Epoxy-activated Sepharose 6B affinity chromatography was used for large-scale purification. The presence of OP and CB pesticide residues in agricultural samples was assayed on the basis of AchE inhibition value. The presence (6 bands) or absence of some colored bands on the test line indicated a negative or positive result, respectively. The limits of detection for measured organophosphorus (OP) and carbamates (CB) pesticide residues in standard pesticide solutions and fortified samples were ranged from 0.50 to 2.50 ppm and 0.50 to 4.75 ppm, respectively.

• Applied Biological Chemistry
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• v.50 no.2
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• pp.107-110
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• 2007

The putative laccase gene, yacK of Escherichia coli, K-12 is not expressed in lab culture conditions. The laccase gene was amplified by PCR and subcloned into pET28a vector. The laccase overproduced in E. coli harboring pET28a was purified by His-affinity column chromatography. The purified laccase, which has the apparent molecular weight of 55,000 on the SDS-polyacrylamide gel showed enzyme activity on the guaiacol solution and agar plate. Optimum temperature and pH were around 65$^{\circ}C$ and 5.0, respectively.

• 한국생물공학회:학술대회논문집
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• 2003.10a
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• pp.533-533
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• 2003

• Proceedings of the Korean Magnetic Resonance Society Conference
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• 2002.08a
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• pp.67-67
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• 2002

• Journal of the Korean Society of Clothing and Textiles
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• v.22 no.4
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• pp.477-481
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• 1998

Colored components in black tea were extracted, freeze-dried, and analysed to investigate the possibility using as a natural dye. Fractionation of the colored components was carried out by gel permeation chromatography. The colored components in black tea were elected into seven fractions. Each fraction was analyzed by UV spectrophotometer. The early fluted fractions 1-4 did not show any absorption peaks in 320-700 nm and showed the increase in absorption as it approaches to short wavelength and are considered as highly polymerized colored substances. Fractions 5-6 showed tar at 350 m and are considered as thearubigins. Fraction 7 showed absorption peaks at 376 nm and 456 nm and is considered as theaflavin. IR spectra of each fraction show: Strong C=0 stretching band at 1650 cm-1 appears in fractions 1-4, but not in fractions 5-7. Strong C=0 stretching band at 1700 cm-L appears in fraction 3-7. C=0 stretching band at 1610 cm-1 appears as a shoulder in fraction 4 and progressively changes into strong peak in fraction 5-7. From these results, it is assumed that colored components in black tea consist of polyphenolic substances having different molecular weight which were formed during tea manufacturing process. The colorants from black tea infusion were applied to silk, wool, cotton and nylon fabrics. Black tea colorants showed high affinity to wool, silk and nylon, but very low affinity to cotton fabrics.

• Journal of Microbiology and Biotechnology
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• v.30 no.1
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• pp.127-135
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• 2020

Small RNAs (sRNAs) are widespread and play major roles in regulation circuits in bacteria. Previously, we have demonstrated that transcription of esrE is under the control of its own promoter. However, the regulatory elements involved in EsrE sRNA expression are still unknown. In this study, we found that different cis-regulatory elements exist in the promoter region of esrE. We then screened and analyzed seven potential corresponding trans-regulatory elements by using pull-down assays based on DNA affinity chromatography. Among these candidate regulators, we investigated the relationship between the ferric uptake regulator (Fur) and the EsrE sRNA. Electrophoresis mobility shift assays (EMSAs) and β-galactosidase activity assays demonstrated that Fur can bind to the promoter region of esrE, and positively regulate EsrE sRNA expression in the presence of Fe²⁺.