• Journal of Yeungnam Medical Science
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• v.10 no.2
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• pp.360-368
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• 1993

GTP binding protein (G-protein) associated with membrane and involved in signal transduction was isolated from bovine brain, and molecular weight of G protein was observed. As the results, cell membranes were homogenized from bovine brain tissues and proteins of membrane were gained using 1% cholate, and progressed the chromatography. The purification process was performed by step, DEAE-Sephacel, Ulttrogel AcA 34 and heptylamine-Sepharose column chromatography. The chromatographic fractions were confirmed by GTP binding assay and SDS-polyacrylamide gel electrophoresis. Molecular weight of $Go{\alpha}$ was revealed 39,000 dalton and $G{\beta}$ 36,000 dalton. One more step of heptylamine-Sepharose was enforced to purify the GTP binding protein. Finally I gained the GTP binding protein isolated subtype of $Go{\alpha}$ and $G{\beta}$.

• Journal of Life Science
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• v.8 no.4
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• pp.416-420
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• 1998

Soybean sprouts peroxidase can be used for enzymatic determination of glucose. Peroxidase from soybean sprouts was purified by ammonium sulfate precipitation and DEAE Sephacel column chromatography. The glucose could be quantitatively assayed by using glucose oxidase and soybean sprouts peroxidase. The optimum pH and temperature for glucose assay were of pH 5.5 and $40^{\circ}C$, respectively. The relationship between absorbance and glucose concentration was linear. And also the relationship between absorbance and reaction time was linear. The reducing agents such as L-cysteine, dithiothreitol inhibited the glucose assay by glucose oxidase and soybean sprouts peroxidase.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1998.11a
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• pp.161-161
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• 1998

To achieve the aim of this investigation, the extracellular protease was isolated from bacteria BAC-4, a strain was cultivated in the medium for the production of penicillin acilase in a period of 32 hours. The enzyme was first purified by aceton precipitation method, followed by ion exchange chromatography on DEAE-sephacel column. The highest specific activity of the aceton fraction was found to be 2.19 unit per mg, with degree of purification of 13 times. Further purification of the enzyme on DEAE -sephacel had a specific activity of 58.6 unit per mg and degree of purification of 344 times compared to its crude extract. The optimum pH of the enzyme was 8.4, and the potimum temparature was 37$^{\circ}C$. The K$\_$M/ and $V_{max}$ calculated at experiment conditions were found to be 0.66%(W/V) and 3.61 unit per mL respectively.

• Proceedings of the Korean Society for Food Science of Animal Resources Conference
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• 1996.11a
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• pp.92-92
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• 1996

• YAKHAK HOEJI
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• v.41 no.2
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• pp.212-219
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• 1997

Multiple forms of extracellular phospholipase $A_2$ have been detected in human amniotic fluid (HAF). When HAF was subjected to heparin-Sepharose column chromatography, phospholipase $A_2$ activity was detected in both heparin-non binding and binding fraction. The activity of heparin-non binding fraction was further purified by sequential uses of column chromatographies on butyl-Toy-opearl 650M and DEAE-Sephacel. DEAE-Sephacel fraction contained three different phospholipase $A_2$ activities (Peak I, II, III). The molecular weight of DEAE-Sephacel fraction phospholipase $A_2$ determined by SDS-PAGE were about 52KDa (Peak I). Peak II, III required micromolar $Ca^{2+}$ ion for its maximum activity, but Peak I enzyme showed calcium independent phospholipase $A_2$ activity and showed broad range of pH (6.0~10.0) optimum. All these enzymes were not recognized by a monoclonal antibody raised against phospholipase $A_2$ from human synovial fluid. These results suggest that HAF might contain multiple forms of extracellular phospholipase $A_2$, which may neither belong to the 14KDa group II phospholipase $A_2$ family nor cytosolic phospholipase $A_2$.

• KSBB Journal
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• v.15 no.2
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• pp.145-149
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• 2000

Methyl mercaptan oxidase was isolated and purified from Thiobacillus thiooxidans KCTC2505 for the detection of mercaptans. T The produre of purification involved DEAE-Sephacel and Superose 12 column chromatographies with recovery yields of 40 a and 6.3%, and specific activity of 19.7 and 80.1 units/mg-protein, respectively. The molecular weight of purified methyl m mercaptan oxidase was determined to be 68.1 kDa by SDS-PAGE. The extract from DEAE-Sephacel column chromatography h had a high activity in oxidizing methyl mercaptan to produce formaldehyde which can be easily detected by purpald-coloring m method. Optimum temperature for activity was observed at $43^{\circ}C$. This enzyme was activated by $NH_4CI and (NH_4)_2S0_4$, and | inhibited by KCI and NaC!.

• Microbiology and Biotechnology Letters
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• v.16 no.4
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• pp.320-326
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• 1988

Glucoamylase (EC 3.2.1.3) of Aspergillus sp. isolated from soil was partially purified by Sephacryl S-200 gel filtration and DEAE-Sephacel ion exchange chromatography, The glucoamylase activity was separated into two isozymes after DEAE-Sephacel ion exchange chromatrography. The optimum pH and temperature for both glucoamylase isozymes (GI, GII) were identical; pH 4.5 and temperature, $65^{\circ}C$. The molecular weights of GI and GII Isozymes were estimated to be 105,000, which were measured by gel filtration on Sephacryl S-200. Both isozymes were stable at pH ranges of 2 to 7, and up to 6$0^{\circ}C$. Glycerol was effective to stabilize the both isozymes. The activation energies of GI and GII isozymes were 10.63 and 10.33 kcal/mole, respectively. The enzyme activities of both isozymes were completely inactivated by addition of 0.1% Hg$^{++}$. In kinetic studies, the Km values of GI isozyme for soluble starch, dextrin, and glycogen were 0.62%, 0.32%, and 1.02%, respectively. For GII isozyme, they became 0.66%, 0.23%. and 0.14% for the substrates.

• Journal of Environmental Science International
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• v.7 no.6
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• pp.853-857
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• 1998

Purification of the isocitrate lyase extracted from Microbacterium laevaniformans was investigated. The isocitrate lyase was purified 43.6 folds by the following continuous treatment with ammonium sulfate fraction, DEAE-cellulose, DEAE-sephacel and Sephadex G-200 chromatography. The purified isocitrate lyase was showed to be a single protein band by polyacrylamide gel electrophoresis. The molecular weight of the purified isocitrate lyase was estimated 54,000 Da by the SDS-polyacrylamide gel electrophoresis. The Km and Vmax values for isocitrate were estimated to be 0.83mM and 0.33units/ml, respectively. Activity of isocitrate lyase was inhibited by cystein-HCl and glutathione.

• 한국생물공학회:학술대회논문집
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• 2000.04a
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• pp.485-488
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• 2000

Methyl mercaptan oxidase was isolated and purified from Thiobacillus thioparus TK-m for the detection of mercaptans. The procedure of purification involved DEAE-Sephacel and Superose 12 column chromatographies with recovery yields of 47.5 and 48.5 %, and specific activity of 374 and 1240.8 units/mg-protein, respectively. The molecular weight of purified methyl mercaptan oxidase was determined to be 66.1 kDa by SDS-PAGE. Optimum temperature for activity was observed at $55\;^{circ}C$. This enzyme was activated by $(NH_4)_2SO_4$ and NaCl and inhibited by $NH_4Cl$.

• Microbiology and Biotechnology Letters
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• v.20 no.1
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• pp.40-45
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• 1992

Acidic nucleotidase from Asfiergilius nlger has been partially purified by Sepharose CL-6B gel filtration and DEAE-Sephacel ion exchange chromatography. The optimum pH and temperature for the enzyme reaction with 5'-AMP or 3'-AMP as a substrate were 4.5 and 55%, respectively. However, the optimum temperature became 70% when p-nitrophenyl phosphate was used as a substrate. The enzyme was stable at acidic pH. The enzyme activity was not affected by addition of various nucleotides, nucleosides and inorganic phosphates. Ferric, aluminium, vanadate and molybdate ions inhibited the enzyme activity dramatically. In kinetic studies, $K_m$), values for 3'-AMP, 5'-AMP and p-nitrophenyl phosphate were 1.39 mM, 1.5 mM and 5.77 mM, respectively. The substrate efficiency ($V_{max}/K_m$) shows 3'-AMP is the prefered substrate for the enzyme among tested substrates.