• Korean Journal of Microbiology
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• v.38 no.2
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• pp.81-85
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• 2002

A marine bacterium producing superoxide dismutase, strain number B446, was screened with nitrite quantitation method using hydroxy amine and photochemically generated superoxide ion, and the superoxide dismutase was purified through 35-75% ammonium sulfate precipitation, DEAE-Sephadex A-25 ion exchange chromatography, Sephadex G-200 gel filtration chromatography, and High-Q anion exchange chromatography to a yield of 6% and purification fold of 32.3.

• 대한핵의학회:학술대회논문집
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• 1972.11a
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• pp.72.1-72.1
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• 1972

• Korean Journal of Microbiology
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• v.37 no.3
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• pp.182-188
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• 2001

The glucoamylase was purified from the induced culture filtrate of hybrid between Saccharomycopsis sp. and Saccharomycopsis sp. made by nuclear transfer and characterized for some enzyme properties. The enzymewas purified 76-fold in an overall yield of 16% from the culture medium by ammonium sulfate fractionation,Sephadex G-150 gel permeation chromatography and DEAE-Sephadex A-50 ion exchage chromatography.The molecular weight of the purified glucoamylase was estimated to be 57.5 KDa on SDS-polyacrylamidegel electrophoresis and Sephadex G-150 gel permeation chromatography. The purified enzyme was active atpH-5.0 and $40^{\circ}C$. The Km value for soluble starch was 2.6 mg/ml. The enzymatic activity was stimulated inthe presence of TEX>$Ca^{2+}$, EDTA, $Co^{2+}$, $Mg^{2+}$, and $Mn^{2+}$

• Microbiology and Biotechnology Letters
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• v.11 no.1
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• pp.47-52
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• 1983

The extracellular inulase produced by Aspergillus sp. C-58 was isolated by pH and charcoal treatment, precipitation with ammonium sulfate from the crude extract, and separated into 3 fractions (P-I, II, III) by DEAE-cellulose column chromatography in the ratio of 31.1:1.7:1 with respect to the activity. The ratio of inulase activity to sucrase activity of P-I, P-II and P-III fraction was 0.23, 0.24 and 1.1 respectively. The enzyme P-I fraction was purified 482 fold with a 22.8% yield by DEAE-Sephadex A-50, Sephadex G-75, Sephadex G-100 (1st and 2nd) column chromatography, and appeared homogeneous on polyacrylamide disc gel electrophoresis and ultracentrifugation.

• Microbiology and Biotechnology Letters
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• v.19 no.1
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• pp.57-63
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• 1991

A strain J-19 was isolated from soil, produced lipase which has resistant against alkali and linear alkylbenzene sulfonate. The strain was identified as Pseudornonns sp.. The enzyme was purified by ammonium sulfate precipitation, DEAE-Sephadex and Sephadex G- 100 column chromatography. The specific activity of the purified enzyme was 35 unit/mg protein and the yield of enzyme activity was 17%. The purified enzyme showed a single band on polyacrylamide disc gel electrophoresis. Mo1ecul;tr weight of the purified enzyme was estimated about 36,000 by Sephadex GI00 gel filtration and SDS-polyacrylarnide gel electrophoresis. The optimum pH and temperature were pH 10.0 and $30^{\circ}C$, respectively. Activity of the purified enzyme was increased 2-fold by the addition of 0.1% linear alkylbenzene sulfonate and 2.5- fold by the addition of 0.05% Tide. This enzyme remained stable from pH 8.0 to 10.0 and stable up to $40^{\circ}C$.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.25 no.6
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• pp.501-510
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• 1992

Lipid prooxidants in sardine skin was characterized. Prooxidants in the sardine skin extract with 0.05M phosphate buffer was purified by successive chromatography on Sephadex G-200, DEAE-Sephadex A-50 and CM-Sephadex A-50. Prooxidants of sardine skin exist mainly in the intermediate molecular weight fractions. Observations of the thermounstability and optimum pH(pH 7.0) suggest that the major prooxidants are enzymes and hemoproteins. They can oxidize well both free and esterified linoleic acid and form conjugated hydroperoxides. From these results, the major prooxidants in sardine skin are assumed to be lipoxygenase-like enzymes.

• Microbiology and Biotechnology Letters
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• v.16 no.4
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• pp.259-264
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• 1988

Two forms of extracellular inulinase, designated as PI and PII were detected in the crude enzyme preparation from n species of Pseudomonas isolated from soil. PI and PII were purified to homogeneity by ammonium sulfate fractionation, DEAE Sephadex A-50 chromatography, Sephadex G-100 and Sephadex G-200 gel filteration. Both isoenzymes catalyzed specifically and endowise the cleavage of the $\beta$-2,1-fructofranoside linkage of inulin, and displayed no action upon sucrose, raffinose and levan. The optimal pH values for the PI and PII enzyme were pH 5.5 and 6.0, respectively and the highest activity of the two enzymes was observed at 55$^{\circ}C$. The Km values of PI and PII were calculated to be 2$\times$10$^{-3}$M and 5$\times$10$^{-3}$M, respectively.

• The Korean Journal of Mycology
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• v.10 no.2
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• pp.67-73
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• 1982

The $(NH_4)_2\;SO_4$ (70%) treated crude enzymes from the culture filtrates of the$C-7^{+t}$ strain of Pyricularia oryzae which was grown on 2% CMC (carboxymethyl cellulose) for 8 days at $28^{\circ}C$ were chromatographied on Sephadex G-150 and DEAE-Sephadex A-25 columns. From the chromatography, three fractions of CMCase$(C_x)$ was examined using Na-CMC as substrate. The $C_x$ enzyme activity was optimal at pH 6.0 and $40^{\circ}C$, stable up to $40^{\circ}C$. The values of Km and Vmax of the enzyme were $2.8{\times}10\;mM$ and 5.9m moles/hour, respectively. The molecular weight determined by Sephadex G-150 column chromatography was around 80,000. Approximately sevenfold purified $C_x$ enzyme gave a single protein band on the polyacrylamide gel electrophoresis.

• Korean Journal of Food Science and Technology
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• v.8 no.3
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• pp.141-146
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• 1976

1) The purified enzyme was obtained with the specific activity 126.5 u/mg protein (about 45 times of the original activity) and the yield of 4.2%, by means of salting out with ammonium sulfate (0.5 saturation) of the crude enzyme solution, desalting by Sephadex G 25, CM cellulose columm chromatography, concentration by Sephadex G 25, and gel filtration by Sephadex G 75. 2) In the acrylamide gel disc electrophoresis of the purified enzyme, the main band and two obscure ones on the both side of the main band appeared, which indicated that the enzyme was considerably purified compared with its crude enzyme solution, even if it is not referred to as a pure protein.

• Korean Journal of Microbiology
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• v.25 no.3
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• pp.180-183
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• 1987

Stu I, type II restriction endonuclease, has been purified to homogeneity from Streptomyces tubercidicus (ATCC 25502), and its catalytic properties have been studied. For the purification of Stu I endonuclease free of nonspecific nucleases, DEAE-Sephadex (A-50), QAE-Sephadex (A-50) and Heparin-agarose column chromatography have been performed after ammonium sulfate fractionation of the crude extract. The enzyme was further purified by gel filtration using Sephadex G-100 column to obtain homogeneous form of protein. The single polypeptide species of Stu I endonuclease has a subunit molecular weight of 34,000 $\pm$ 1,000 daltons as judged by polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate. Stu I endonuclease requires $Mg^{2+}$ ion for its activity and is maximally active at neutral pH (7.0-8.0) in the absence of NaCl.