• 대한의생명과학회지
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• 제10권4호
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• pp.347-351
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• 2004

Maggot fibrolase (MsMg-1) was purified from the maggots of Mimela splendems using ammonium sulfate fractionation, DEAE Affi-gel affinity chromatography. This protease had a molecular weight of 85 kDa as determined by SDS-polyacrylarnide gel electrophoresis under reducing conditions. It showed strong proteolytic and fibrinolytic activities. The purified enzyme was strongly inhibited by phenylmethanesulfonyl fluoride, Mn/sup 2+/, and Zn/sup 2+/ but it was not by EDTA, EGT, Mg/sup 2+/, Ca/sup 2+/, and Li/sup 2+/ ions. In these experimental results, we have speculated that MsMg-1 is a serine protease with a strong fibrinolytic activity.

• Bulletin of the Korean Chemical Society
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• 제32권7호
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• pp.2405-2409
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• 2011

The psychrophilic bacteria Psychromonas arctica survives at subzero temperatures by having adapted several protective mechanisms against freezing and oxidative stresses. Many reactive oxygen species are likely generated in P. arctica as a result of reduced metabolic turnover rates. A previous study identified the pasod gene for superoxide dismutase from P. arctica using a series of PCR amplifications. Here, upon cloning into a His-tag fused plasmid, the sod gene from P. arctica (pasod) was successfully expressed by IPTG induction. His-tagged PaSOD was subsequently purified by $Ni^{2+}$-NTA affinity chromatography. The purified PaSOD exhibited a higher SOD activity than that of Escherichia coli (EcSOD) at all temperatures. The difference in activity between PaSOD and EcSOD becomes even more significant at 4$^{\circ}C$, indicating that PaSOD plays a functional role in the cold adaptation of P. arctica in the Arctic.

• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 1992년도 제1회 신약개발 연구발표회 초록집
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• pp.24-24
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• 1992

담자균류인 말징버섯 Calvatia craniformis의 성분을 연구하기 위하여 그 균사체를 액내 배양하여 열수 추출한 후 ethanol로 침전시켜 단백 결합 다당체를 분리하였다. 이 성분을 DEAE-cellulose ion exchange, Sepharose CL-4B gel filtration 그리고 Concanavalin A Sepharose 4B affinity chromatography를 실시하여 총 6가지 분획(Fr. A~F)으로 정제하였다. 이들을 각각 10또는 20mg/kg/day의 용량으로 마우스의 복강에 투여하였을때, 육종 180 고형암에 디하여 41.7~74.1%의 종양억제율을 나타내었고 $\beta$-형 다당체인 Fr. F가 종양 억제율이 가장 높았다. 화학 분석에 의해, 이 성분은 4기의 단당 mannose, xylose, galactose, glucose로 구성된 87.2% polysaccharide와 1.9%의 Protein 및 1.3%의 hexosamine 함유하고 있고 이 성분의 분자량은 5.5 $\times$ $10^4$ dalton이었다. 이 성분을 calvatan이라 명명 하였다.

• 한국미생물생명공학회:학술대회논문집
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• 한국미생물생명공학회 1979년도 추계학술대회 심포지움
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• pp.243.3-244
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• 1979

Low molecular weight endo-glucanase fraction of cellulase from Trichoderma reesei was purified using Sephadex G-100 and concanavalin A-Sepha-rose 4B affinity chromatography. Its biochemical characteristics including pH profile, temperature profile and kinetic behavior were studied. The optimum conditions for enzymatic reaction were pH 6.0 and $5^{\circ}C.$ The activation energy for CMC (carboxymethylcellulose) was 10,800 cal/mole. Its adsorption to amorhous and crystalline cellulose was observed. Adsorption to amorphous cellulose was more rapid and greater than that of crystalline cellulose. Reconstitution study was performed. Significance of low molecular weight endo-glucanase on cellulose hydrolysis will be further discussed.

• 한국식품영양과학회지
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• 제26권5호
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• pp.844-850
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• 1997

$\alpha$-Galactosidase was partially purified from the culture filtrate of pichia guilliermondii by Mannobiose-Sepharose affinity column chromatography. The galactosidase exhibited maximum activity at pH 4.5 and 4$0^{\circ}C$, and was stable in the pH and temperature ranges of 4 to 5.5 and 30 to 6$0^{\circ}C$, respectively. The enzyme was inhibited by $Hg^{2+}$ and $Ag^{2+}$. The enzyme activity was ot affected considerably by treatment with other metal compounds. The enzyme hydrolyzed melibiose to galactose and glucose, raffinose to galactose and sucrose, and $Gal^{3}Man_{3}(6^{3}-$\alpha$-galactosyl-1,4-mannotriose)$ to galactose and mannotriose. On the contrary, it could not hydrolyze $Gal^{3}Man_{4}(6^{3}-galactosyl-1,4-$\alpha$-mannotetraose)$.

• BMB Reports
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• 제43권9호
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• pp.609-613
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• 2010

The Dvl and Axin proteins, which are involved in the Wnt signaling pathway, each contain a conserved DIX domain in their sequences. The DIX domain mediates interaction between Dvl and Axin, which together play an important role in signal transduction. However, the extremely low production of DIX domain fragments in E. coli has prevented more widespread functional and structural studies. In this study, we demonstrate that the DIX domains of Dvl and Axin are expressed noticeably in a multi-cistronic system but not in a mono-cistronic system. Formation of the $DIX_{Dvl1}-DIX_{Axin1}$ complex was investigated by affinity chromatography, SEC and crystallization studies. Unstable DIX domains were stabilized by complexing with counterpart DIX domains. The results of the preliminary crystallization and diffraction of the $DIX_{Dvl1}-DIX_{Axin1}$ complex may prove useful for further crystallographic studies.

• 한국약용작물학회:학술대회논문집
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• 한국약용작물학회 2007년도 추계학술발표회
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• pp.281.2-281.2
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• 2007

• Biotechnology and Bioprocess Engineering:BBE
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• 제2권2호
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• pp.86-89
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• 1997

Epidermal growth factor(EGF) known as a urgastrone is a powerful mitogen with a wide variety of possibilities for medical usages. A mature EGF coding region was isolated from human prepro-EGF sequence by a conventional PCR and cloned into pQE vector in which the gene product was supposed to be expressed with 6$\times$His tag for the subsequent purification. The recombinant mature EGF was expressed in M15[Rep4], an Escherichia coli host strain, in amount of 30-40% of total proteins pressent in E. coli extract by the addition of isopropylthio-$\beta$-galactopyranoside (IPTG). The recombinant EGF purified using a Ni2+-NTA affinity colume chromatography was active in its ability to induce phosphorylation on tyrosine residues of several substrate proteins when murine NH3T3 and human MRC-5 fibroblast cells were stimulated with it. This work may provide the basic technology and information for the production of recombinant EGF.

• Journal of Microbiology and Biotechnology
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• 제17권4호
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• pp.681-684
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• 2007

An immunoassay method was developed to quantitatively detect phosphinothricin-N-acetyltransferase (PAT) encoded by the Bialaphos resistance (bar) gene in genetically modified (GM) pepper. The histidine-tagged PAT was overexpressed in Escherichia coli M15 (pQE3l-bar) and efficiently purified by $Ni^{2+}$ affinity chromatography. A developed sandwich enzyme-linked immunosorbent assay (S-ELISA) method (detection limit: $0.01{\mu}g/ml$) was 100-fold more sensitive than a competitive indirect ELISA (CI-ELISA) method or Western blot analysis in detecting the recombinant PAT. In real sample tests, PAT in genetically modified herbicide-tolerant (GMHT) peppers was successfully quantified [$4.9{\pm}0.4{\mu}g/g$ of sample (n=6)] by the S-ELISA method. The S-ELISA method developed here could be applied to other GMHT crops and vegetables producing PAT.

• 한국식물병리학회지
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• 제10권4호
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• pp.277-283
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• 1994

An antimicrobial chitinase was purified from grapefruit extract and its properties were characterized. The chitinase was purified with a single step chromatography on regenerated chitin affinity gel column. The molecular weight of the purified chitinase was 29 kDa. The grapefruit extract contained the chitinase protein more than 50% of its total soluble proteins measured by coomassie stained protein bands. When the purified chitinase was incubated with polymers of N-acetylglucosamine (NAG), such as mycelia of Fusarium oxysproum and swollen chitin, they were degraded to oligosaccharides, and the oligosaccharides were then further hydrolyzed by the same enzyme to monomer and dimer of NAG. This result suggests that the chitinase contained both endo- and exo- chitinase activities. The chitinase was stable to heat and pH treatment; its activity was not diminished by the heat treatment upto 7$0^{\circ}C$ for 1 hr, and it showed a pH stability in the range of pH 4.0 to 12.0.