• Journal of Microbiology and Biotechnology
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• v.18 no.7
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• pp.1216-1220
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• 2008

Sequence analysis of the metabolically rich genome of Streptomyces peucetius ATCC 27952 revealed a 2,199 bp sesquiterpene alcohol (germacradienol) synthase-encoding gene from the germacradienol synthase/terpene cyclase gene cluster. The gene was named spterp13, and its putative function is as a germacradienol synthase/terpene cyclase. The amino acid sequence of Spterp13 shows 66% identity with SAV2163 (GeoA) from S. avermitilis MA4680 and 65% identity with SCO6073 from S. coelicolor A3(2), which produces germacradienol/geosmin. The full-length recombinant protein was heterologously expressed as a his-tagged fusion protein in Escherichia coli, purified, and shown to catalyze the $Mg^{2+}$-dependent conversion of farnesyl diphosphate to the germacradienol, which was verified by gas chromatography/mass spectrometry.

• Journal of Microbiology and Biotechnology
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• v.18 no.5
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• pp.946-951
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• 2008

The opd gene, encoding organophosphorus hydrolase (OPH) from Flavobacterium sp. capable of degrading a wide range of organophosphate pesticides, was surface- and intracellular-expressed in Synechococcus PCC7942, a prime example of photoautotrophic cyanobacteria. OPH was displayed on the cyanobacterial cell surface using the truncated ice nucleation protein as an anchoring motif. A minor fraction of OPH was displayed onto the outermost surface of cyanobacterial cells, as verified by immunostaining visualized under confocal laser scanning microscopy and OPH activity analysis; however, a substantial fraction of OPH was buried in the cell wall, as demonstrated by proteinase K and lysozyme treatments. The cyanobacterial outer membrane acts as a substrate (paraoxon) diffusion barrier affecting whole-cell biodegradation efficiency. After freeze-thaw treatment, permeabilized whole cells with intracellular-expressed OPH exhibited 14-fold higher bioconversion efficiency ($V_{max}/K_m$) than that of cells with surface-expressed OPH. As cyanobacteria have simple growth requirements and are inexpensive to maintain, expression of OPH in cyanobacteria may lead to the development of a low-cost and low-maintenance biocatalyst that is useful for detoxification of organophosphate pesticides.

• Journal of Soil and Groundwater Environment
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• v.19 no.3
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• pp.47-55
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• 2014

Arthrobacter chlorophenolicus A6 possesses several monooxygenases (CphC-I, CphC-II, and CphB) that can catalyze the transformation of 4-chlorophenol (4-CP) to hydroxylated intermediates in the initial steps of substrate metabolism. The corresponding genes of the monooxygenases were cloned, and the competent cells were transformed with these recombinant plasmids. Although CphC-II and CphB were expressed as insoluble forms, CphC-I was successfully expressed as a soluble form and isolated by purification. The specific activity of the purified CphC-I was analyzed by using 4-CP, 4-chlorocatechol (4-CC), and catechol (CAT) as substrates. The specific activities for 4-CP, 4-CC, and CAT were determined to be 0.312 U/mg, 0.462 U/mg, 0.246 U/mg, respectively. The results of this study indicated that CphC-I is able to catalyze the degradation of 4-CC and CAT in addition to 4-CP, which is a primary substrate. This research is expected to provide the fundamental information for the development of an eco-friendly biochemical degradation of aromatic hydrocarbons.

• Journal of Microbiology
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• v.33 no.3
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• pp.201-207
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• 1995

We have previously reported that SPP2 gene product of yeast Saccharomyces cerevisiae is involved in the pre-mRNA splicing. To investigate the rol ein the splicing pathway of the Spp2p protein, the SPP2 gene was overexpressed in Escherichia coli and polyclonal antibodies to Spp2p were generated from rabbits. First, a DNA fragment containing the SPP2 GENE without its promoter was subcloned into an E. coli expression vector, pKK233-3. The resulting recombinant plasmid pBQ14 contained an IPTG inducible tac promoter and the SPP2 structural gene. Overexpression of the SPP2 gene was achieved by additionof 0.1 to 1.0 mM IPTG to a logarithmic culture of E. coli JM103(pBQ14) for 90 min at 37.deg.C. Sequence of N-terminal 15 amino acids of the overproduced protein was well matched to the deduced one from the SPP2 reading frame. Then, polyclonal antibodies were generated from rabbits immunized with gel-purified SppSp protein. These antibodies reacted specifically with the Spp2p protein extracted from yeast cells expressing the SPP2 gene to a great extent. The antibodies could also block the activity of yeast splicing extracts.

• Journal of Physiology & Pathology in Korean Medicine
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• v.17 no.4
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• pp.1065-1074
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• 2003

In order to evaluate the antiallergic effects of Kamiyukgunja-tang (KYGJT), studies were done. We measured the cytotoxic activity for lung fibroblast cell, cytokines transcript expression, production of INF-γ, IL-10, IL-4, GM-CSF, IL-1 β, TNF-α. IL-5 proliferation of B cell in anti-CD40mAb plus r1L-4 stimulated murine splenic B cells. The results were obtained as follows : 1. KYGJT was not showed cytotoxicity in the fibroblast lung cell. 2. KYGJT increased the gene synthesis of INF-γ, IL-10, GM-CSF(m-RNA). 3. KYGJT decreased the gene synthesis of IL-1β, IL-4, TNF-α, IL-5(m-RNA). 4. KYGJT decreased the appearance of TNF-α significantly. 5. KYGJT decreased the appearance of IgE significantly. 6. KYGJT decreased the proliferation of B cell significantly. 7. KYGJT decreased the appearance of Histamin Release Production significantly. The facts above prove that KYGJT is effective against the allergy. Thus. I think that we should study on this continuously

• Journal of Life Science
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• v.22 no.3
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• pp.306-311
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• 2012

A gene encoding a lipase, lipT, was cloned from the psychrotrophic bacterium Pseudomonas mandelii and sequenced. An open reading frame of 1,686 bp was found that encodes a polypeptide consisting of 562 amino acid residues. Sequence analysis revealed a Gly-His-Ser-Leu-Gly sequence, which matches the consensus Gly-X-Ser-X-Gly motif conserved among lipolytic enzymes. The recombinant LipT protein was predominantly expressed as inclusion bodies in Escherichia coli and subsequently purified by nickel-chelate affinity chromatography. A small fraction of LipT was refolded, and the subsequent LipT exhibited substrate preferences for p-nitrophenyl butyrate (C4) and p-nitrophenyl octanoate (C8).

• Journal of fish pathology
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• v.34 no.2
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• pp.177-184
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• 2021

Vaccines based on single-cycle viruses that are replication-incompetent due to knockout of replication-related structural gene(s) are more immunogenic than inactivated or subunit vaccines and can be used as delivery vehicles for foreign antigens without concerns on the reverting to virulent forms. The aim of this study was to develop a delivery vehicle for nervous necrosis virus (NNV)-like particles (VLPs) using G gene deleted single-cycle VHSV (rVHSV-𝚫G). Recombinant single-cycle VHSVs carrying NNV capsid protein gene between N and P gene of rVHSV-𝚫G genome (rVHSV-𝚫G-NNV_Cap) were rescued by reverse genetic technology. The successful expression of NNV capsid protein in cells infected with rVHSV-𝚫G-NNV_Cap was demonstrated by Western blot analysis, and the production of NNV VLPs in infected cells was confirmed using an electron microscopy. The results suggest that single-cycle VHSVs can be used as a safe delivery vehicle for NNV VLPs, and can be extended to other pathogens for the development of prophylactic vaccines.

• Journal of Microbiology and Biotechnology
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• v.28 no.12
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• pp.2029-2035
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• 2018

Cycloisomaltooligosaccharide glucanotransferase (CITase) was isolated from alkaliphilic Paenibacillus daejeonensis via an amino acid homology search for the reported CITase. The recombinant alkaliphilic CITase (PDCITase) from P. daejeonensis was expressed in an Escherichia coli expression system and purified as a single protein band of 111 kDa. PDCITase showed optimum activity at pH 8.0 and retained 100% of activity within a broad pH range (7.0-11.5) after 18 h, indicating alkaliphilic or alkalistable CITase properties. In addition, PDCITase produced CI-7 to CI-17, CI-18, and CI-19, which are relatively large cycloisomaltooligosaccharides yet to be reported. Therefore, these large cycloisomaltooligosaccharides can be applied to the improvement of water solubility of pharmaceutical biomaterials.

• Journal of The Korean Society of Grassland and Forage Science
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• v.40 no.4
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• pp.285-290
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• 2020

To understand the role of small heat shock protein (sHSPs) in rice plant response to various stresses such as the heat and oxidative stresses, a cDNA encoding a 24.1 kDa mitochondrial small HSP (Oshsp24.1) was isolated from rice by rapid amplification of cDNA ends (RACE) PCR. The deduced amino acid sequence shows very high similarity with other plant small HSPs. DNA gel blot analysis suggests that the rice genome contains more than one copy of Oshsp24.1. High level of expression of Oshsp24.1 transcript was observed in rice seedlings in response to heat, methyl viologen, hydrogen peroxide, ozone, salt and heavy metal stresses. Recombinant OsHSP24.1 protein was produced in E. coli cells for biochemical assay. The protein formed oligomeric complex when incubated with Sulfo-EGS (ethylene glycol bis (succinimidyl succinate)). Our results shows that Oshsp24.1 has an important role in abiotic stress response and have potential for developing stress-tolerant plants.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2020.10a
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• pp.220-220
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• 2020

Astaxanthin, a natural carotenoid component of shrimp, has been used as a food additive for the treatment of various diseases, but a functional role of Astaxanthin Nanosphere (AN) in the regulation of intestinal mucin (Muc) 2 production during bacterial infection has not described yet. In this study, we have investigated the effect of AN prepared from astaxanthin during Muc2 repression elicited by the Gram-negative bacterium V. vulnificus in human gastrointestinal epithelial (HT-29) cells. AN significantly inhibited the level of ROS production and PKC activation in recombinant protein (r) VvpE-stimulated HT-29 cells. Moreover, AN inhibited the PKC-mediated phosphorylation of extracellular signal-regulated kinase and nuclear factor-kappa B responsible for region-specific hypermethylation in the Muc2 promoter in rVvpE-treated HT-29 cells. In the mouse models of V. vulnificus infection, treatment with AN maintained the level of Muc2 expression in the intestine. On the basis of these results, we suggest that AN blocks the hypermethylation of the Muc2 promoter to restore the level of Muc2 production in HT-29 cells infected with V. vulnificus.