• Korean Journal of Microbiology
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• v.36 no.2
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• pp.109-111
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• 2000

A 3.5 kb plasmid from Lactobacillus. casei ssp. cosei NCIB 4114 was isolated and E. cali-L. casei shuttle vectors were constructed containing this plasmid. Transformation by electroporation was successful with all the plasmids constructed. Optimized condition for the electroporation was established with efficiency level of $2{\times}10^5$ transformants per $\mu$g of vector DNA. Successful introduction of those shuttle vectors enable to these vectors as food grade vector for lactic acid bacteria.

• The Korean Journal of Physiology
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• v.28 no.2
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• pp.233-240
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• 1994

In this study, it was investigated whether immortalized proximal tubule cells transformed with pRSVT could survive through the numerous passages. Results were as follows: 1. The cells transfected with pRSVT formed rapidly growing, multilayered colonies within 2 weeks in a hormone defined medium. Domes were also observed in some of the cultures. 2. r-glutamyl transpeptidase activity was equivalent to that observed in primary renal proximal tubule cell cultures. 3. Transformed cells with pRSVT form tubules in matrigel following 20 passages. 4. Genomic DNA of transformants was digested with either the restriction enzyme Xba or BamH1. A band of approximately 7.5kb was detected with Xba. Three BamH1 bands were detected at approximately 15 kb, 6.5 kb, and 3 kb.

• Microbiology and Biotechnology Letters
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• v.16 no.2
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• pp.126-130
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• 1988

Promoters of an alkali-tolerant Bacillus sp. isolated from soil have been cloned in Bacillus subtilis using promoter probe vector pPL703. The CAT specific activity of a clone harboring the strongest promoter activity among these transformants was 8.01. This activity was 2.5 times higher than that of Bacillus subtilis harboring expression vector pPL708 and was increased after the end of the logarithmic growth phase. In the 2.8kb of inserted DNA fragment, BamHI and Sal I recognition sites were located.

• Journal of Ecology and Environment
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• v.30 no.3
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• pp.257-264
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• 2007

Over-expression of a copper/zinc superoxide dismutase (Cu/ZnSOD) resulted in substantially increased tolerance to cadmium exposure in Arabidopsis thaliana. Lower lipid peroxidation and $H_2O_2$ accumulation and the higher activities of $H_2O_2$ scavenging enzymes, including catalase (CAT) and ascorbate peroxidase (APX) in transformants (CuZnSOD-tr) compared to untransformed controls (wt) indicated that oxidative stress was the key factor in cadmium tolerance. Although progressive reductions in the dark-adapted photochemical efficiency (Fv/Fm) and quantum efficiency yield were observed with increasing cadmium levels, the chlorophyll fluorescence parameters were less marked in CuZnSOD-tr than in wi. These observations indicate that oxidative stress in the photosynthetic apparatus is a principal cause of Cd-induced phytotoxicity, and that Cu/ZnSOD plays a critical role in protection against Cd-induced oxidative stress.

• Biomedical Science Letters
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• v.18 no.1
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• pp.29-34
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• 2012

Streptomycetes are gram-positive filamentous bacteria that are well-known for producing a vast array of bioactive compounds, including more than 70 % of commercially important antibiotics. For the research about Streptomyces sp., the protoplast and electroporation transformation method have been the general techniques for the construction of transformants. However, these techniques have low efficiency and are time-consuming. Another option is intergenic conjugation, which is used for DNA transfer using methylation-deficient E. coli as a DNA donor to avoid the methylated-DNA-dependent restriction systems of actinomycetes. This conjugation method has been widely improved and applied to many other actinomycetes. In this research, an effective transformation procedure for the construction of expression vector by using gateway system was established to avoid limit of restriction enzyme site for cloning of target gene based on transconjugation by Escherichia coli ET12567/pUZ8002 with a pSET152 integration vector.

• Journal of Plant Biology
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• v.37 no.1
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• pp.17-25
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• 1994

Two potato (Solanum tuberosum L.) cultivars were transformed by Agrobacterium tumefaciens harboring cauliflower mosaic virus (CaMV) 35S promoter and $\beta$-glucuronidase (GUS) gene. Expression patterns of the CaMV 35S promoter according to tissue types and developmental stages, and genetic stability of GUS gene were investigated in the clonal progenies of transgenic potatoes. Kanamycin-resistant shoot emerged from tuber disc after 4 weeks of culture, and root was induced 6 weeks after culture on the selection medium. Shooting frequency of cvs. Superior and Dejima were 43% and 27%, respectively. Mature transformants and their clonal progenies showed no phenotypical abnormality. GUS activity was expressed primarily at parenchymatous cells of phloem tissue around the vascular cambium in the stem and root, and higher activity was found at the apical meristem of shoot, root and adventious shoot bud. GUS activity was higher at tubers of young explants than at stored tubers. These facts indicate that expression level of the CaMV 35S promoter differed according to tissue types and developmental stages of the organs. The GUS gene was stably inherited to each clonal progeny and normally expressed.

• Proceedings of the Microbiological Society of Korea Conference
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• 2000.10a
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• pp.85-91
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• 2000

Aspergillus oryzae is a filamentous fungus classified in the group Aspergillaceae Ascomycetes. It is an important microorganism for industrial production of enzymes and fermented food productions. It secrets large quantities of proteins or enzymes into the culture medium which makes this organism appealing for the production of heterologous proteins. Recently Electric field-mediated transformation method, electroporation, has been applied to fungal transformation. In this study, fungal transformation was carried out by bypassing the protoplast isolation step, decreasing the culturing time and non-protoplast transformation for the increment of transformation efficiency. Transformants were obtained with electroporation in optimal condition 2,500 voltage, 1,540 ohm and 0.50 capacitance. More than 1,000 transform ants were obtained with 6-10 hrs cultured mycelia without enzyme treatment, called non-protoplast transformation.

• Journal of Microbiology
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• v.33 no.4
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• pp.344-349
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• 1995

The alkalophilic bacterium, Xanthomonas sp. JK311, producing extracellular proteases, was isolated from soil. Xanthomonas sp. JK311 produced five extracellular proteases that are all metalloproteases. Four of them were resistant against 1% SDS. Chromosomal DNA of the Xanthomonas sp. JK311 was digested with BamHI and cloned into PUC19. Among E. coli strain HB101 transformants, a clone secreting the proteases was screened through halo formation on skim-milk agar plate and by Southern blot analysis. It had the recombinant plasmid pXEP-1 containing the 7.5 kb-BamHI DNA fragment and produced three extacellular proteases. Their protease properties corresponded to those of Xanthomonas sp. JK311.

• Biotechnology and Bioprocess Engineering:BBE
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• v.3 no.1
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• pp.48-49
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• 1998

A protocol for the transformation of Klebsiella oxytoca by electroporation was developed. Preparation of competent cells at early exponential phase was most critical to obtain high transformation efficiency. The highest efficiency of 1.6$\times$106 transformants per $\mu\textrm{g}$ DNA(pBR322) could be obtained by electroporation of K. oxytoca cells prepared at the OD600 of 0.2 with 1.25$\mu\textrm{g}$ DNA at the filed strength of 2.5kV, the parallel resistance of 200$\Omega$ and capacitance of 25$\mu$F.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.47 no.2
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• pp.116-122
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• 2002

Dehydrins (LEA Dll proteins) are one of the typical families of plant proteins that accumulate in response to dehydration, cold stress, abscisic acid, or during seed maturation. A 1.3-kb cDNA was cloned from a cDNA expression library of 5-day-old germinating maize scutellums under drought stress. The deduced protein sequence indicated a dehydrin gene encoding SK$_3$ LEA protein typically expressed during cold acclimation, but not by drought stress in barley and wheat. Thus, it was named maize DEHYDRIN2 (ZmDhn2). It accumulates rapidly and highly in drought-stressed scutellum and leaf tissues at any stage, but not under cold stress. ZmDhn2 gene was transformed into Arabidopsis thaliana for functional analysis under drought condition. From electrolyte leakage test, no significant difference showed between wild type and transformants under normal growth condition, but the leakage level of electrolyte in wild type plants was about 3 times as high as that in the transformed plants under drought stress. It suggests that ZmDHN2 playa role in increasing drought tolerance.