• Microbiology and Biotechnology Letters
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• v.14 no.2
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• pp.181-186
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• 1986

A defective lambda transducing phase carrying acetyl CoA carboxylase gene (fabE) from Escherichia coli chromosome (72 min on the current linkage map) has been isolated. A restriction map of the chromosomal region from defective transducing phage was established by digestion with combination of the restriction enzymes. No cleavage site for the enzyme EcoRI was found in this region. Restriction fragments were cloned from defective transducing phage into high copy number plasmid vector pACYC184 to generate hybrid plasmids which were capable of complementation of fabE temperature sensitive mutation. We show here that the fabE gene is located on a 3.4 megadalton Bam HI-SalI fragment with a HindIII site, which lies within the 7.4 megadalton BglIIfragment, by complementation analysis.

• Journal of Periodontal and Implant Science
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• v.32 no.3
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• pp.603-614
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• 2002

Human gingival fibroblasts have proven to useful as a species specific cell culture system in various system on periodontal disease and regeneration. However, their use is limited, since they are hard to obtain and lifespan is short due to replicative senescence. To overcome these disadvantages, we transfected primary human gingival fibroblasts by the E6 and E7 genes of the Human papilloma virus(HPV) 16. The full length of HPV 16 E6 and E7 was cloned from the pBR322 into BamHl and Sal I of a pBabe vector including hygromycin B resistance. Before pBabeE6/E7 plasmid transfection, peak 8 GFP including G418 resistance was transfected into primary GF to check the transfection efficency. PBabe E6/E7 plasmid was transfected using Lipofectamine plus following manufacter's instruction into primary normal human gingival fibroblasts in 60mm dishes with FBS free DMEM. After 2 days of transfection, the cells were treated with hygromycin for 2 weeks until the transfected control cells died. The resulting hygromycin resistant colonies were pooled, and clonned, and sucessful　transfection was established for immortalized gingival fibroblast cell lines. Immoralized GF cells showed stellate shape, that is similar to that of orange grains, and more rapid growth and higher proliferation than that of primary gingival fibroblasts. This cell lines overcame crisis and could be cultured over 30 subcultured, could be use for three dimentional culture, epithelial-mesenchymal interaction study.

• Microbiology and Biotechnology Letters
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• v.33 no.2
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• pp.96-105
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• 2005

For screening of autoregulator receptor gene from Streptomyces longwoodensis, PCR was performed with primers of receptor gene designed on the basis of amino acid sequences of autoregulator receptor proteins with known function. PCR products were subcloned into the BamHIsite of pUC19 and transformed into the E. coli $DH5{\alpha}$. The isolated plasmid from transformant contained the fragment of 100 bp, which was detected on $2\%$ gel after BamHI treatment. The insert, 100 bp PCR product, was confirmed as the expected internal segment of gene encoding autoregulator receptor protein by sequencing. Southern and colony hybridizations with the 100 bp fragment as a probe allowed to select a genomic clone of S. longwoodensis, pSLT harboring a 4.4 kb SphI fragment. Nucleotide sequencing analyses revealed a 651 bp open reading frame(ORF) were isolated protein showing moderate homology ($35{\sim}46\%$) with the ${\Gamma}$-butyrolactone autoregulator receptors from Streptomyces sp., and this ORF was named sltR The sltR/pET-17b plasmid was constructed to overexpress the recombinant SltR protein (rSltR) in E. coli BL21 (DE3)/pLysS, and the rSltR protein was purified to homogeneity by DEAE-Sephacel column chromatography, and DEAE-5PW chromatography (HPLC). The molecular mass of the purified rSltR protein was 55 kDa by HPLC gel-filtration chromatography and 28 kDa by SDS-PAGE, indicating that the rSltR protein is present as a dimer. A binding assay with tritium-labeled autoregulators revealed that the rSltR has clear binding activity with a A-factor type autoregulator as the most effective ligand.

• Microbiology and Biotechnology Letters
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• v.14 no.2
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• pp.155-160
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• 1986

$\alpha$-Amylase gene of B. amyloliquefaciens was cloned to E. coli-yeast shuttle vector YEp-13 and expressed in E. coli. Chromosomal DNA of B. amyloliquefaciens was partially digested with Sau3Al and YEp13 plasmid was cleaved with BamH1. The hybrid plasmid, pHA28, was constructed by shotgun method and transformed to E. coli C600 and HB101. The amount of $\alpha$-amylase produced by transformants of E. coli was about 20% to 30% of that produced by B. amyloli-quefaciens. About 65% of $\alpha$-amylase produced by transformant was secreted into periplasm and the others were located in cytoplasm. $\alpha$-Amylase production was maximal when transformants were cultivated for 15hr to 20hr. As the result of agarose gel electrophoresis, pHA28 plasmid was found to be various in its size. This result suggested that pHA28 plasmid was segregated.

• Microbiology and Biotechnology Letters
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• v.24 no.4
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• pp.415-422
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• 1996

A gene coding for a pyruvyl transferase enzyme involved in exopolysaccharide biosynthesis of Zoogloea ramigera 115SLR was isolated and sequenced. A 4.5 kb of BamHI DNA fragment was isolated from chromosomal DNA using a probe derived from ketal pyruvyl transferase gene of Xanthomonas campestris. The nucleotide sequence of 2.66 kb Pst1/HindIII DNA fragment which was homology with a probe revealed the existence of two complete open reading frames (ORF2 and ORF3) and two partial open reading frames (ORFI and ORF4). The deduced amino acid sequence of ORF3 was homologous to the ketalase (GumL product) of X campestris with 49.5% of similarity and 21.6% of identity. ORF2 on the other hand showed the higher identity with the ketalase (ExoV product) of Rhizobium meliloti (36%) as well as the ketalase of X campestris (23%) than that of ORF3. A gene product of ORF2 was determined with a bacteriophage T7 RNA polymerase/promoter system in E. coli. The molecular weight of protein was 33,500 dalton.

• Asian-Australasian Journal of Animal Sciences
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• v.8 no.5
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• pp.449-454
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• 1995

The present study was conducted to assess gene expression of bacterial lacZ driven by the SV40 promoter at early developmental stages of bovine embryos. The lacZ gene was linearized with BamHI digestion and introduced into the pronucleus by microinjection at 20 hrs after the commencement of in vitro fertilization. Intact bovine blastocysts were not stained with X-Gal, suggesting that there is no endogenous beta-galactosidase activity in these blastocysts. In contrast, the bovine blastocyst cells microinjected with the lacZ gene exerted a characteristic greenish-blue color originating from the bacterial beta-galactosidase activity, albeit at a low rate, i.e. 2.1% of the total fertilized oocytes injected. It was concluded, therefore, that the lacZ gene driven by the SV40 promoter could be used for an indirect screening method in which the presence of transgene is evaluated from the product of transgene expression.

• Asian-Australasian Journal of Animal Sciences
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• v.12 no.2
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• pp.215-219
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• 1999

This study aims to make detail examination of smallholder dairy farming systems in the Nongpho Dairy Cooperative. Forty-three dairy farms were selected from three geographical areas i.e. irrigated area, municipality area, and factory area. Within each area some number of sample farms were selected from each of the three levels of farm and animal crowdedness (very crowded, crowded, and not crowded farms). Detail data were collected during 1996 to 1997, they were socio-economic conditions of the sample farms and farmers, dairy production systems and management of resources (animals, bam, feeds, stocking rates, herd structure, animal body conditions, milk yield and milk quality, manure and farm wastes management, and other related items). Detail information useful for the improvement of farm production efficiency were discussed. It was very clear that much improvement of smallholder dairy production can be achieved if the recommendations given by this study were implemented.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.02a
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• pp.312-312
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• 2013

GaN based light emitting diodes (LEDs) are important devices that are being used extensively in our daily life. For example, these devices are used in traffic light lamps, outdoor full-color displays and backlight of liquid crystal display panels. To realize high-brightness GaN based LEDs for solid-state lighting applications, the development of p-type ohmic electrodes that have low contact resistivity, high optical transmittance and high refractive index is essential. To this effect, indiumtin oxide (ITO) have been investigated for LEDs. Among the transparent electrodes for LEDs, ITO has been one of the promising electrodes on p-GaN layers owing to its excellent properties in optical, electrical conductivity, substrate adhesion, hardness, and chemical inertness. Sputtering and e-beam evaporation techniques are the most commonly used deposition methods. Commonly, ITO films on p-GaN by sputtering have better transmittance and resistivity than ITO films on p-GaN by e-bam evaporation. However, ITO films on p-GaN by sputtering have higher specific contact resistance, it has been demonstrated that this is due to possible plasma damage on the p-GaN in the sputtering process. In this paper, we have investigated the advanced sputtering using plasma damage-free p-electrode. Prepared the ITO films on the GaN based LEDs by e-beam evaporation, normal sputtering and advanced sputtering. The ITO films on GaN based LEDs by sputtering showed better transmittance and sheets resistance than ITO films on the GaN based LEDs by e-beam evaporation. Finally, fabricated of GaN based LEDs by using advanced sputtering. And compared the electrical properties (measurement by using C-TLM) and structural properties (HR-TEM and FE-SEM) of ITO films on GaN based LEDs produced by e-beam evaporation, normal sputtering and advanced sputtering. As a result, It is expected to form plasma damage free-electrode, and better light output power and break down voltage than LEDs by e-beam evaporation and normal sputter.

• Microbiology and Biotechnology Letters
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• v.14 no.2
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• pp.161-168
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• 1986

A 1.95Kb Sau3Al fragment coding for $\alpha$-amylase from Bacillus amyloliquefaciens was isolated by the shotgun method using Escherichia coli as a host. The genome of Bacillus amyloliquefaciens was partially digested with the restriction endonuclease Sau3Al and joined to plasmid YRp7 cleaved with the restriction endonuclease BamHI. The $\alpha$-amylase gene present in a 1.95Kb insert was stably maintained and expressed in Escherichia coli. The amount of $\alpha$-amylase activity produced by Escherichia coli containing the hybrid plasmid pEA24 was about 65% of the activity produced by the donor Bacillus amyloliquefaciens strain. The properties of $\alpha$-amylase produced by Escherichia coli were very similar to those produced by Bacillus amyloliquefaciens as based on optimum temperature, pH, and effect of CaCl$_2$ concentration. About 70% of the $\alpha$-amylase produced by Escherichia coli was localized in the periplasmic space, whereas the remaining enzyme was localized in the inner part of the cell.

• Microbiology and Biotechnology Letters
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• v.18 no.6
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• pp.640-646
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• 1990

We have cloned the cdd gene from E. coli C600 using (cdd-) as a host. From the sequenced promoter region of E=, coli cdd gene which has been determined by Valentin-Hansen P. (1985), we synthesized the 23 mer oligonucleotides corresponding to the transcription initiation region and used as a probe for cloning of the cdd gene by Southern blotting. The isolated fragments in the blotting were introduced to the colony hybridization after transforming it into the E. coli JF611 (cdd-, pyr double mutant), and we identified the hybridized band at 27 kb long. From the original insert of 27 kb fragment in theBamHI site of pBR322, the 5.3 kb fragment containing the cdd gene was isolated by subsequent deletion and subeloning. From the derived plasmid pTK509, further deletion and subcloning were performed and clarified that the cdd gene was located in the 2.1 kb of SaZI/DraI segment in the insert of pTK605. The polypeptide encoded by the cloned DNA was appeared to be a molecular mass of 33,000.