• Journal of Microbiology and Biotechnology
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• 제16권2호
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• pp.299-302
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• 2006

A combinatorial library of artificial transcription factors (ATFs) was introduced into the bacterial cells that expressed the Akt1-GFP fusion protein. By measuring the level of fluorescence generated by the transformed E. coli cells, we were able to obtain clones in which ATFs increased the solubility of the Akt1. Our results show that ATF library is a useful tool for increasing the solubility of selected recombinant proteins in E. coli.

• Journal of Microbiology and Biotechnology
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• 제12권5호
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• pp.841-843
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• 2002

Pfu DNA polymerase from Pyrococcus furiosus was expressed in the E. coli periplasm, and the fully active polymerase was partially purified by applying osmotic shock, ammonium sulfate precipitation, and heat treatment. This method represents a new way of expressing and purifying functional Pfu DNA polymerase without the use of chromatography.

• Parasites, Hosts and Diseases
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• 제42권4호
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• pp.195-200
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• 2004

We investigated the induction of resistance to Haemaphysalis longicornis infestation in rabbits that had been immunized with recombinant H. longicornis P27/30 protein. The success of immunological control methods is dependent upon the use of potential key antigens as tick vaccine candidates. Previously, we cloned a gene encoding 27 kDa and 30 kDa proteins (P27/30) of H. longicornis, and identified P27/30 as a troponin I-like protein. In this study, rabbits that were immunized with recombinant P27/30 expressed in Escherichia coli showed the statistically significant longer feeding duration for larval and adult ticks (P<0.05), low engorgement rates in larval ticks (64.4%), and an apparent reduction in egg weights, which suggest that H. longicornis P27/30 protein is a potential candidate antigen for a tick vaccine. These results demonstrated that the recombinant P27/30 protein might be a useful vaccine candidate antigen for biological control of H. longicornis.

• 산업기술연구
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• 제36권
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• pp.33-37
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• 2016

Cellulose binding domains (CBDs) of cellulases are thought to assist in the hydrolysis of insoluble crystalline cellulose. To gain sufficient amount of CBDs, the self-cleavable intein tag was used for expression and purification of Trichoderma reesei cellobiohydrolase I CBD in E. coli. Synthetic CBD genes, CBD or linker-CBD were cloned into expression vector pTYB11. Recombinant CBDs were successfully purified by intein mediated purification with an affinity chitin-binding domain. The final yields of recombinant CBD and linker-CBD were 3.2 mg/L and 1.4 mg/L, respectively. The functional bindings of recombinant CBDs were confirmed by Avicel binding experiments. The simple and easy purification method using self-cleavable intein tag can be further used in pretreatment of crystalline cellulose or characterization of engineered CBDs.

• 한국어병학회지
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• 제28권2호
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• pp.93-98
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• 2015

Full-length recombinant VP2 and VP3 proteins of aquabirnavirus isolated from olive flounder were expressed successfully in E. coli expression system. After rats were immunized with these proteins, antisera were used for in vitro and in vivo neutralization test. In in vitro test, VP2 antibody titers were higher than that of VP3. In in vivo assays, fish challenged with aquabirnavirus neutralized with VP2 antibody survived longer than other fish.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2001년도 추계학술발표대회
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• pp.719-722
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• 2001

Silk proteins from Nephila clavipes are fibrous proteins containing repetitive sequences with both crystalline and amorphous domains. In order to obtain high-level production of silk protein, the synthetic genes had 16 contiguous units of the consensus repeat sequence of the silk protein were expressed in Escherichia coli BL21(DE3) under the strong inducible T7 promoter. For production of recombinant silk protein in large amounts, pH-stat fed-batch cultures were carried out. The recombinant silk protein was produced as soluble forms in E. coli, and the recombinant silk protein content was as high as 11% of the total protein. When cells were induced at $OD_{600}$ of 60, the amount of silk protein produced was 6.49 g/L. After simple purification steps, 9.2 mg of silk protein that was more than 80% pure was obtained from a 50 mL culture, and the recovery yield was 26.3%.

• Biomolecules & Therapeutics
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• 제1권2호
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• pp.166-170
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• 1993

Hirudin is a potent inhibitor of thrombin, which was originally obtained from the medicinal leech (Hirudo medicinalis) Now it is being produced through the recombinant technology on a large scale. Recombinant hirudin has been assayed for the anticoagulant activity by the measurement of clotting time and the inhibition of thrombin actvity using a chromogenic substrate. The assay range of partial thromboplastin time and thrombin time is within $0.2{\sim}1.0 {\mu}g/mι.$ Thrombin time is more sensitive to the measurement of clot. Ex vivo study showed the level of hirudin in rat plasma was highest in 10 min and then it was eliminated slowly. The half-life of r-hirudin was 80~110 min depending on the assay methods. Intraveneous injection of russel viper venom was used for thrombus induction combined with vents cava ligation. Inhibition of venous thrombosis was observed with i.v. hirudin. It was dependent on the concentration of hirudin.

• Biotechnology and Bioprocess Engineering:BBE
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• 제10권4호
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• pp.353-356
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• 2005

The effect of silkworm hemolymph on the expression of recombinant protein in Escherichia coli was investigated. The addition of silkworm hemolymph to the culture medium in­creased the production of recombinant $\beta$-galactosidase in E. coli. The production was dependent on the concentration of the added silkworm hemolymph, which increased 2-, 5-, and 8-fold in media supplemented with 1, 3, and $5\%$ silkworm hemolymph, respectively. To identify the effective component, the silkworm hemolymph was fractionated by gel filtration column chromatography. A fraction, with a molecular weight of about 30 K was identified as the effective component.

• BMB Reports
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• 제32권3호
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• pp.247-253
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• 1999

Chicken egg ovalbumin is a non-inhibitory member of the serpin (serine protease inhibitors) family whose members share a common tertiary fold. In the present study, we succeeded in high-level production of a disulfide-free form of refolded recombinant ovalbumin. Conformational characterization of the recombinant ovalbumim revealed that it is well-folded, following two-state unfolding transition with the midpoint of transition at 4.7 M at $25^{\circ}C$. This value is very close to that of the reduced form of authentic ovalbumin. The recombinant ovalbumin can serve as a model molecule of non-inhibitory serpins in comparative studies with inhibitory members of the serpin family.

• 식물조직배양학회지
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• 제27권4호
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• pp.283-297
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• 2000

Seeds are an ideal repository for recombinant proteins in molecular farming applications. However, in order to use plant seeds efficiently for the production of such proteins, it is necessary to understand a number of fundamental biological properties of seeds. This includes a full understanding of promoters which function in a seed-specific manner, the subcellular targeting of the desired polypeptide and the final form in which a protein is stored. Once a biologically active protein has been deposited in a seed, it is also critical that the protein can be extracted and purified efficiently. In this review, these issues are examined critically to provide a number of approaches which may be adopted for production of recombinant proteins in plants. Particular attention is paid to the relationship between subcellular localization and protein extraction and purification. The robustness and flexibility of seed-based production is illustrated by examples close to or already in commercial production.