• KSBB Journal
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• v.13 no.1
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• pp.96-100
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• 1998

Two promoters (trc and P$\rho$) were inserted in PHA operon derived from Alcaligenes eutrophus to obtain high chain molecules of polyhydroxybutyrate (PHB) in recombinant Escherichia coli. Newly designed PHA operon was used to control the gene expressions of hydroxybutyric CoA and PHA polymerization, separately. Plasmids containing new synthetic operon was transformed into E. coli DH5$\alpha$ and analyzed for PHB production. Without induction of the PHA biosynthetic operon, PHA synthase which has low activity might supply low concentration of initiator during the polymerization reaction, resulting very high molecular weight of polymer. An increase of PHB average molecular weight was observed with decreased IPTG (isopropyl $\beta$ -Dithiogalactosidase) concentration. When no IPTG was added to the culture of E. coli DH5$\alpha$ /$\rho$ SJS1 which contained two promoters in PHA operon, high chain polymer having an average molecular weight of $2.5{\times}10^7$ was achieved. Analysis of the enzyme activities of PHA biosynthetic enzymes suggests that PHA synthase, the enzyme responsible for polymerizing 3-hydroxybutyric CoA, controls the molecular weight of PHB produced in vivo.

• Journal of Plant Biotechnology
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• v.43 no.2
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• pp.223-230
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• 2016

Ascorbic acid (AsA) is a strong antioxidant/reducing agent that can be converted to dehydroascorbate (DHA) by oxidation in plants. DHA, a very short-lived chemical, is recycled to AsA by dehydroascorbate reductase (DHAR). Previously, DHAR cDNA was isolated from the hairy roots of the sesame plant, and DHAR-overexpressing transgenic potato plants were generated under the control of the CaMV35S promoter (CaMV35S::DHAR). An increase in transgene expression and ascorbate levels were observed in the transgenic plants. In the present study, proteomic analysis revealed that transgenic plants not only accumulated DHAR in their cells, but also induced several other antioxidant enzyme-related proteins during plant growth. These results suggest that DHAR is important for stress tolerance via induction of antioxidant proteins, and could improve stress tolerance in transgenic potato plants.

• Microbiology and Biotechnology Letters
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• v.15 no.6
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• pp.396-401
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• 1987

Protein productivities of a cloned gene ($\beta$-galactosidase) and the cultural performances of two recombinant Escherichia coli strains, which use different host-vector systems, were studied. E. coli JM109/pTBG10 strain which carries Tac promoter had higher protein productivity than E. coli MH3000 (pRKc1857)/pASI(lacZ) strain which carries pL promoter. Induction of protein syn-thesis was optimum at the initial-and mid-logarithmic growth phases for both strains. Oxygen demand was observed to be very high during the cloned gene expression, and could be alleviated to some extent through pH control. The ratio of specific growth rates of plasmid-harboring to plasmidfree cell, $\mu$+ /$\mu$-, of the high productivity strain was observed to be lower than that of the low productivity one. Plasmid stability was analyzed for 20-30 generations, and it was found that the traction of plasmid-harboring cells dropped to l0% level in about 25 generations for both strains when the cloned gene expression was induced.

• Tuberculosis and Respiratory Diseases
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• v.64 no.6
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• pp.466-470
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• 2008

A factor VII gene -401 G/A polymorphism was identified in a patient with a pulmonary embolism. The patient was a 71-year-old woman who presented with acute-onset dyspnea. A chest CT scan revealed a pulmonary embolism. Despite the administration of low-dose warfarin as anticoagulation therapy, there was an excessively prolonged prothrombin time (PT). The blood tests revealed lower factor VII activity than normal. Full factor VII gene sequencing revealed a G to A substitution at -401 in the promoter region. There were no other gene sequence anomalies. PCR-based analysis indicated lower factor VII gene expression in the patient than in a control subject. The data suggested the promoter polymorphism to be responsible for the lower transcription level. In conclusion, we encountered a case of Factor VII DNA polymorphism in a patient with a pulmonary embolism showing significantly reduced Factor VII activity.

• Korean journal of applied entomology
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• v.38 no.2
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• pp.145-149
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• 1999

To develop the baculovirus expression vector system (BEVS) adopting p10 gene promoter of Spodoptera exigua nucleopolyhedrovirus (SeNPV), we characterized the p10 gene of SeNPV. The nucleotide sequence of 545 bases including the coding region of p10 gene was determined. Compared with the previously reported SeNPV p10 gene (Zuidema et al., 1993), 4 bases were different in the 5' and 3' flanking region but no difference was found in the coding region. The p10 gene was located within Xho I 1.5 Kb, Sph 1 2.4 Kb and Cla I 4.0 Kb fragments by Southern hybridization analysis. Also, the Sph I 2.4 Kb and the Cla I 4.0 Kb fragments were cloned and their restriction enzyme maps were determined.

• Journal of Plant Biotechnology
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• v.45 no.4
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• pp.364-368
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• 2018

The R2R3-type protein IbMYB1 transcription factor is a key regulator for anthocyanin biosynthesis in the storage roots of sweet potatoes. It was previously demonstrated that the IbMYB1 expression stimulates anthocyanin pigmentation in tobacco leaves, arabidopsis and storage roots of sweet potatoes. In this study, we generated the transgenic potato plants that express the IbMYB1 genes, which accumulated high levels of anthocyanins under the control of either the tuber-specific patatin (PAT) promoter or oxidative stress-inducible peroxidase anionic 2 (SWPA2) promoter. The PAT-MYB1 transgenic lines exhibited higher anthocyanin levels in the tuber than the empty vector control (EV) or SWPA2-MYB1 plants. When combined, our results indicated that overexpression of the IbMYB1 is a highly promising strategy for the generation of transgenic plants with enhanced tissue specific anthocyanin production.

• Microbiology and Biotechnology Letters
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• v.26 no.6
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• pp.537-544
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• 1998

The cultivation conditions of transformant Alcaligenes eutrophus AER5 harboring cloned phbC gene for mass production of poly (3-hydroxybutyrate-3-hydroxyvalerate)[P(3HB-3HV)] containing high molar fraction of 3-hydroxyvalerate (3-HV) were investigated. In two-stage batch cultivation, transformant accumulated P(3HB-3HV) containing 52.2 mol% of 3HV compared to 30 mol% of parent strain A. eutrophus H16. The increased 3-HV molar fraction was due to the amplified activity of PHB synthase participating in condensation of 3-HB and 3-HV. To increase efficiency of P(3HB-3HV) accumulation, fructose was added along with precursor compound valerate, and total cell mass and P(3HB-3HV) concentrations remarkably increased, but not 3-HV molar fraction. The effect of magnesium ion showed that P(3HB-3HV) concentration and 3-HV molar fraction were significantly increased upto 6.1 g/L and 71.3 mol% at 0.01 g/L of MgSO$_4$, respectively. The efficiency of several pH adjuster, NaOH, NaOH and (NH$_4$)$_2$SO$_4$, and NH$_4$OH, on total cell mass, p(3HB-3HV) concentration, and 3-HV molar fraction was also compared. To overcome the disadvantage of two-stage cultivation, one-stage intermittent fed-batch cultivation was attempted, such a way 10.0 g/L of fructose was supplied for cell growth at initial 36 hr and then 10.0 g/L of valerate and 5.0 g/L of fructose were applied to induce the accumulation of P(3HB-3HV), consequently, 10.4 g/L of P(3HB-3HV) with 38 mol% of 3-HV fraction could be obtained after 72 hr. These results can be used for elucidating cultivation strategy for mass production of P(3HB-3HV) containing high 3-HV molar fraction using transformant A. eutrophus AER5 harboring cloned phbC gene.

• Microbiology and Biotechnology Letters
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• v.32 no.2
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• pp.110-116
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• 2004

The over-expression in E. coli of the pHLN1-SO(＋) and pHLN2-80(－) plasmids cloned an insecticidal crystal protein (ICP) gene (crylAal type) from Bacillus thuringiensis var. kurstaki HD 1 was investigated through in part, the deletion of -80 bp promoter and an alternative change of cloning vector system. Two recombinant plasmids were constructed in an attempt to analyze the over-expression of the ICP in relations to its gene structure possessing only -14 bp ［Shine-Dalgarno (SD) sequence of -80 bp promoter］. Also, anther two recombinant plasmids similarly cloned the icp gene in a different vector system. The amounts of ICP produced from the recombinants were measured by SDS-PAGE and confirmed by Western blot analysis. One clone, pHLRBS1-14 clone in which only the SD sequence in the inverted orientation icp gene appeared, was more evident than the pHLRBS2-14 clone in which only the -14 bp SD sequence of the right orientated icp gene was shown to exist. The pHLN2-80(－) clone produced more ICP proteins than the pHLRBS1-14 clone. In the two clones, pHLNUC1-80 right-oriented icp gene and the pHLNUC2-80 clone inverted-orientation icp gene in a new different vector, the pHLNUC2-80 produced more ICP proteins in E. coli system. These results indicate that the P/ac promoter, the inverted icp gene insertion and -80 bp promoter (-66 bp part of the icp gene promoters), were concerned with the expression of the icp gene in the recombinant plasmids. In addition, the expression mechanism might result from the disruption of the transcription-suppressing regions in the promoter regions.

• Proceedings of the Korean Society for Bioinformatics Conference
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• 2003.10a
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• pp.179-182
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• 2003

The Development of promoter recognition systems is a interesting problem in computational biology. In this paper, we introduce a intelligent system fur promoter recognition with multiple decision models using artificial neural networks. We have trained this models with 1871 human promoter sequences and 5230exon and intron sequences. Our system is found to perform better than other promoter finding systems insensitivity and specificity measures. We have tested our system with Chromosome 22 dataset.

• Proceedings of the KSAR Conference
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• 2002.06a
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• pp.61-61
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• 2002

비 반추동물 특히 돼지의 경우 섬유소 소화율이 극히 낮은 것으로 알려져 있다. 따라서 본 연구는 섬유소분해효소유전자 (CelD) 를 췌장특이 프로모터인 rat Elastase Ⅰ 하류에 연결하여 구축된 벡터를 수정란내 미세주입한 후 생산된 형질전환 돼지를 이용하여 섬유소 소화능력을 측정하기 위하여 실시하였다. 먼저 35두의 수란돈으로 부터 65 두의 산자를 생산하였으며, PCR 분석 결과 4두가 형질전환돼지로 판명되었으며 이중 3두가 죽고, 생존한 l두를 다시 southern blot 분석결과 형질 전환된 것으로 판단하여 같은 복의 6두와 함께 섬유소 소화율을 측정하기 위하여 분리사육을 실시하였다. (중략)