• Journal of Life Science
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• v.10 no.1
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• pp.1-5
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• 2000

Pectinase was isolated from culture medium of Bacillus sp. BS-214 and purified 105-fold with 3.4% yield by ammonium sulfate precipitation, gel filteration using Sephadex G-75 and DEAE-cellulose followed by gel filteration through Sephadex G-100. The molecular weight of the purified enzyme was estimated to be about 43 kDa on SDS-PAGE and by gel filtration, indicating that the enzyme is a monomer. the optium pH and temperature of the enzyme were 9.0 and 55$^{\circ}C$, respectively. the enzyme was stable at 60$^{\circ}C$ for 30min and in a pH range from 7.5 to 10.5 for 12 h ant 4$^{\circ}C$. The enzyme activity was highly enhanced by Ca2+, and also K+, Li+ and Na+showed a positive effect, while stongly inhibited by Zn2+ and Hg2+.

• The Journal of Natural Sciences
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• v.17 no.1
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• pp.55-64
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• 2006

The construction, purification, and characterization of hexahistidine-tagged phage K11 lysozyme are carried out in this study. The results showed that the enzymatic activities of K11 lysozyme are not affected by the purification tag. The optimum pH of K11 lysozyme is 7.2-7.4. The amidase activity of K11 lysozyme was also measured in the presence of different cations. The addition of $Ca^2+$ and $Mg^2+$ almost completely shut down the amidase activity but $Zn^2+$ and $Na^+$ maintained the amidase activity. In the presence of 100 mM $Zn^2+$ the amidase activity was nearly abolished.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.4 no.4
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• pp.72-81
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• 2001

This study is aimed to review the previous research accomplishments with analysis of problems and to suggest the counter plan for the watershed management and the ongoing research strategy. Phytoremediation provides a cost-effective techniques having a merit of low investment and maintenance cost. It could be one of the best techniques, which is an alternative plan to overcome economical situation and lack of experts in our country. In forest watershed affected by waste water and heavy metal pollutants should be controlled by vegetative remediation system, but the disposal techniques of harvested plant materials should be developed. Also, high degree areas of natural vegetation as a key model to recover the vegetation should be well conserved. It is important to restore forest continuity between upper stream and lower stream basin with the restoration of damaged in forest watershed. It is established to integrated protection system for land use and management plan and to natural environment evaluation methods affected by projects such as erosion control and developments in stream and forest. In addition, I suggest the continuous environmental monitoring system to treat the pollutions concerned.

• Korean Journal of Microbiology
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• v.31 no.3
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• pp.237-244
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• 1993

Aspartate aminotransferase (ASAT) (L-aspartate : 2-oxyoglutarate, EC 2.6. 1. 1.) from Streptomyces fradiae NRRL 2702 has been purified by acetone precipitation, DEAE-cellulose, hydroxyapatite, and preparative electrophoresis (Prep cell), of which the last was the most effective step in the purification of ASAT. The molecular mass was estimated to be 54,000 dalton by SDS-PAGE and 120,000 dalton by gel filtration chromatography. Preparative isoelectric focusing of purified ASAT resulted in one polypeptide band with a pI of 4.2, showing homogeneity and indicating that the enzyme is composed of two identical subunits. The enzyme was specific for L-aspartate as an amino donor ; the $K_{m}$ values were determined to be 2.7 mM for L-aspartate, 0.7 mM for 2-oxoglutarate, 12.8 mM for L-glutamate, and 0.15 mM for oxaloacetate. The enzyme was relatively heat-stable, having maximum activity at 55.deg.C, and it had a broad pH optimum ranging from 5.5 to 8.0. The activity of the purified enzyme was not inhibited by ammonium ions. This paper reports the first purification and characterization of the aspartate aminotransferase from a species of Streptomyces.s.

• BMB Reports
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• v.31 no.2
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• pp.144-148
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• 1998

A bifunctional catalase-peroxidase, designated catalase-2, of a UV resistant Deinococcus radiophilus was purified to electrophoretic homogeneity by both chromatographic and electrophoretic methods. Its molecular weight was 310 kDa and composed of a tetramer of 80 kDa subunits. The catalase-2 exerted its optimal activity at $30^{\circ}C$ and around pH 9. Its $K_m$ value for $H_{2}0_{2} $ was about 10 mM. It showed the typical ferric heme spectrum with maximum absorption at 403 nm which shifted to 419 nm in the presence of cyanide. The ratio of A40i' A2S0 was 0.48. Fifty percent inhibition of the enzyme activity was observed at $4.6{\times}10^{-6}$, $7.7{\times}10^{-6}$, and $3.0{\times}10^{-6}$ M of NaCN, $NaN_3$, and $NH_{2}OH$, respectively. The enzyme was thermostable and not sensitive to 3-amino-1,2,4-triazole. Treatment of the enzyme with ethanol-chloroform caused a partial loss (30%) of its activity. The catalase-2 was distinct from the Deinococcal bifunctional catalase-3 in a number of properties, particularly in its molecular structure and substrate affinity.

• Journal of Korean Society of Rural Planning
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• v.6 no.2 s.12
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• pp.43-49
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• 2000

Buffer zone selection technique for natural purification of livestock wastewater within a small agricultural watershed was developed using Geographic Information Systems. The technique was applied to $4.12\;km^2$ watershed located in Gosan-myun, Ansung-gun which have 20 livestock farmhouses. As a necessary data for selecting process, feedlot site map, digital Elevation Model (DEM), stream network, soil and land use map were prepared. By using these data, wastewater moving-path tracing program from each feedlot to the stream was developed to get the basic topographic factors; average slope through the paths, distance to the nearest stream and watershed outlet. To identify the vulnerable feedlots for storm event, the grid-based storm runoff model (Kim, 1998; Kim et al., 1998) was adopted. The result helps to narrow down the suitable area of buffer zone, and finally by using subjective but persuasive conditions related to elevation, slope and land use, the suitable buffer zones were selected.

• Journal of Biomedical Engineering Research
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• v.17 no.3
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• pp.297-304
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• 1996

Although collagen is still considered to be a poor immunogen, animals can produce antibodies to a number of different sites in the collagen molecule. In type I collagen, three classes of antigenic determinants have been described those are recogrlized as different degrees in different species. These are essentially composed of helical, conformation-dependent antigenic determinants and terminal, nonhelical antigenic determinants, and finally central antigenic determinants exposed only after denaturation of the collagen molecule. To utilize collagen as implantable biomateriall human e61bryonic collagen, ten immunological to body, was purified from human umbilical cords and found to contain [$\alpha$1(I)]$_2$. [$\alpha$2(I). Each step of purification were observed by polarized light microscope and analyzed through SDS-PAGE. The conclusious are follows; 1 . The purified collagen revealed gradual fiber indenties on each step of purification by polarized microscope. 2. The structual changes of extracted collagen as removed telopeptide were confirmed by SDS-PAGE.

• Korean Chemical Engineering Research
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• v.51 no.4
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• pp.523-526
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• 2013

In order to purify the waste water containing natural fatty oil, hydroxy radical and/or ozone are used to remove the fatty oil dispersed in the waste water. The fatty oil is decomposed by oxidation reaction through hydroxy radical and ozone, and eliminated as a function of first order reaction. It is clearly confirmed that the fatty oil in waste water can be effectively removed much more in the use of both hydroxy radical and ozone than only hydroxy radical as an oxydant. In addition, the decomposition chemical reaction mechanism of the fatty oil by hydroxy radical and ozone is proposed.

• Journal of Microbiology
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• v.44 no.2
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• pp.185-191
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• 2006

The photosynthetic bacterium, Rhodospirillum rubrum S1, when grown under anaerobic conditions, generated three different types of catalases. In this study, we purified and characterized the highest molecular weight catalase from the three catalases. The total specific catalase activity of the crude cell extracts was 88 U/mg. After the completion of the final purification step, the specific activity of the purified catalase was 1,256 U/mg. The purified catalase evidenced an estimated molecular mass of 318 kDa, consisting of four identical subunits, each of 79 kDa. The purified enzyme exhibited an apparent Km value of 30.4 mM and a Vmax of 2,564 U against hydrogen peroxide. The enzyme also exhibited a broad optimal pH $(5.0{\sim}9.0)$, and remained stable over a broad temperature range $(20^{\circ}C{\sim}60^{\circ}C)$. It maintained 90% activity against organic solvents (ethanol/chloroform) known hydroperoxidase inhibitors, and exhibited no detectable peroxidase activity. The catalase activity of the purified enzyme was reduced to 19 % of full activity as the result of the administration of 10 mM 3-amino-1,2,4-triazole, a heme-containing catalase inhibitor. Sodium cyanide, sodium azide, and hydroxylamine, all of which are known heme protein inhibitors, inhibited catalase activity by 50 % at concentrations of $11.5{\mu}M,\;0.52{\mu}M,\;and\;0.11{\mu}M$, respectively. In accordance with these findings, the enzyme was identified as a type of monofunctional catalase.

• Microbiology and Biotechnology Letters
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• v.18 no.4
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• pp.368-375
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• 1990

Rhodoto& ghtbth~ K-24 was found to produce external invertase in addition to internal and cell wall bound invertase. External invertase was purified to an electrophoretically homogeneous state and partitally characterized and was compared with internal and cell wall bound invertase of which procedures for purification and characterization were reported previously. The enzyme was purified by ethanol precipitation, column chromatographies on DEAE-Sephadex A-50 and SP-Sephadex C-50, and gel filtration on Sephadex G-100. The molecular weight and subunit molecular weight of external invertasGwere estimated to be 220,000 and 100,000, respectively. The isoelectric point of the enzyme was about pH 6.0. The optimum pH and temperature for enzyme activity were pH 4.0 and $60^{\circ}C$, respectively. The enzyme remained stable at the wide range, from pH 3.0 to 11.0 and stable up to $40^{\circ}C$, but was inactivated at temperatures above that. $HgC_12, AgN0_3, MnS0_4$, SDS and p-CMB inhibited the enzyme activity. The $K_m$ value of the enzyme for sucrose was $1.0\times 10^{-2}$M. From these results, the three isozymes from Rh. glutinis K-24 seem to have the similar enzymatic properties, but to differ in molecular and subunit weights.