• Korean Journal of Medicinal Crop Science
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• v.24 no.6
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• pp.464-470
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• 2016

Background: Valeriana fauriei (Valerianaceae) has been used to as a traditional medicine to treat a variety of symptoms, including headache, insomnia, hypertension, and menstrual irregularity. However, the present study investigates the species' antioxidant activity and its inhibition of oxidative DNA damage, which have yet to be studied. Methods and Results: The antioxidant activity was assessed using radical scavenging assays with 1,1-diphenyl-2-picryl hydrazyl (DPPH) and, 2, 2'-azino-bis (3-ethylbenzothiazoline-6 sulfonic acid) diammonium salt (ABTS) and a reducing power assay. The total phenol content was also analyzed, and phenolic compounds were detected using HPLC/UV, whereas the inhibitory effect of Valeriana fauriei on oxidative DNA damage was measured using ${\phi}-174$ RF I plasmid DNA cleavage assay. The DPPH and ABTS radical scavenging activity were $75.17{\pm}3.55%$ and $95.83{\pm}0.63%$, repectively, and the reducing power was $93.14{\pm}1.74$ at $200{\mu}g/m{\ell}$. The total phenol content was $10.24{\pm}0.04mg/g$, whereas chlorogenic acid, catechin, caffeic acid and epicatechin were identified using HPLC/UV, and the ${\phi}-174$ RF I plasmid DNA cleavage assay indicated that V. fauriei provided protection against oxidative damage. Conclusions: The results of the present study suggest that V. fauriei has powerful antioxidant activity that can provide protective effects against the oxidative DNA damage caused by free radicals. The species, therefore, provides a valuable resource for the development of natural pharmaceutical to treat aging, cancer, and degenerative diseases.

• Journal of Microbiology and Biotechnology
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• v.10 no.3
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• pp.312-320
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• 2000

Abstract The full sequence of the plasmid pKJ36, which was derived from Bifidobacterium longum KJ, was determined and analyzed to construct shuttle vectors between E. coli and Bifidobacterium. The plasmid pKJ36 was composed of 3,625 base pairs with a 65.1% G+C content. The structural organization of pKJ36 was highly similar to that of pKJ50, and the three major ORFs on pKJ36 showed high amino acid sequence homologies with those of pKJ50. The putative proteins coded by these three ORFs were designated as RepB (32.0 kDa, pI=9.25), MembB (29.0 kDa, pI=12.25), and MobB (39.0 kDa, pI=IO.66), respectively. The amino acid sequence of RepB showed a 57% identity and 70% similarity with that of the RepA protein of pKJ50. Upstream of the repB gene, the so-called iteron sequence was directly repeated four-and-ahalf times and a conserved dnaA box was identified. An amino acid sequence comparison between the MobB and MobA of pKJ50 revealed a 48% identity and 61 % similarity. A conserved oriT sequence with an inverted repeat identical to that of pKJ50 was also found upstream of the mobB gene. A hydropathy analysis of MembB revealed four possible transmembrane regions. The expressions of the repB and membB genes were confirmed by RT-PCR. The in vitro translation reaction of pKJ36 showed protein bands with anticipated sizes with respect to each putative gene product. S 1 endonuclease treatment and Southern hybridization suggested that pKJ36 replicates by a rolling circle mechanism via a single-stranded DNA (ssDNA) intermediate. A shuttle vector between E. coli and Bifidobacterium sp. was constructed using the pKJ36, pBR322, and staphylococcal chloramphenicol acetyl transferase (CAT) gene. The successful transformation of the Bifidobacterium strains was shown by Southern hybridization and PCR. The transformation efficiency differed from strain to strain and, depending on the electroporation conditions, with a range between $1.2{\times}10^1-2.6{\times}10^2{\;}cfu/\mu\textrm{g}$ DNA.X> DNA.

• Journal of Microbiology and Biotechnology
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• v.11 no.2
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• pp.222-228
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• 2001

Vibrio metschnikovii strain RH530 is a non-pathogenic, industrially-important alkaline protease producer which has been isolated from wastewater. In this paper, we report on the transformation of this strain by using the method of electroporation. A field strength of $7.5\;kVcm^{-1}$ and $25\;{\mu}F$, and using a 0.2-cm cuvette, appeared to be the optimal conditions for electroporation of the cells with the recombinant pSBCm plasmid carrying the vapK alkaline protease gene and the ColE1 replicon. Cells were subjected to osmotic shock in order to remove extracelluar DNase, and adding 200 mM of sucrose to electroporation buffer cells showed an increased transformation efficiency. Maximum efficiency of transformation was obtained at an early exponential growth phase. Using all of the conditions mentioned above, we routinely obtained a transformation efficiency of more than $10^4{({\mu}g\;plasmid\;DNA)}^{-1}$. The stability of the plasmid pSBCm in V. metschnikovii RH530 was 25% after 18h of growth (27 generations) in the medium without antibiotic selection. The insertion of the par locus to the pSBCm increased the stability of the plasmid up to 42% without selective pressure. The increase in plasmid stability was accompanied by the increase in the productivity of alkaline protease in the recombinant V. metschnikovii strain RH530. Determining optimal conditions for the transformation of the industrially-important, nonpathogenic Vibrio strain, and the improvement of plasmid stability by introducing the par locus into the high copy number plasmid vector, will allow the development of procedures involved in the genetic manipulation of this strain, particularly for its use in the production of industrial enzymes such as alkaline protease.

• Journal of Embryo Transfer
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• v.10 no.1
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• pp.91-100
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• 1995

3.3kb 웅성특이 DNA(pEM39 plasmid DNA)가 성 특이 DNA 검색자로 활용되어질 수 있는가를 확인하기 위하여 구조적인 분석을 Southern blotting, DNA sequencing과 computer program 분석을 통하여 실시하였다. 전체 3.3kb에서 유래된 약 1kb 단위의 단편을 이용하여 표지된 짧은 DNA probe들은 Southern blot 분석에서 웅성특이성을 나타내었다. McGraw와 Jeon의 sequence에 대한 유사성 비교 자료로부터 여러 부분의 conserved region을 찾아내고 이것을 기초로 하여 5개의 primer set들을 선발하였다. Conserved region에 존재하면서 computer program에 의해서 선발되어진 PMS1과 2의 primer set가 최종적으로 PCR 분석을 위하여 선정되었다. 이 primer set를 사용한 PCR 분석에서, 1ng부터 10pg까지의 웅성 genomic DNA에서 PCR 산물을 얻을 수 있었으며, 자성의 경우는 어떠한 산물도 찾을 수 없었다. PCR에 이용할 수정란의 시료는 2 세포기의 수정란에서 얻었으며 순수 분리된 genomic DNA에서 확립된 조건에서 PCR을 수행하였다. 8개의 수정란을 분석한 결과 4개의 웅성과 4개의 자성 수정란을 확인하였다. 이러한 결과는 선정된 primer set가 돼지 수정란의 성을 조기 감별하는데 효율적인 DNA probe로 사용될 수 있다는 것을 암시한다.

• Proceedings of the Korean Society for Applied Microbiology Conference
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• 1986.12a
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• pp.518.2-519
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• 1986

토양으로부터 분리한 질소고정균인 Klebsiella pneumoniae NFB320의 chromosomal DNA를 BamHI으로 절단하여 동일한 제한효소로 절단한 pBR322에 ligation시켜 E. coli HB101에 형질전환을 행하여 pullulanase activity를 나타내는 clone을 얻어내었다. 이 형질 전환체로부터 분리한 pullulanase 유전자가 재조합된 plasmid DNA는 약 10kb의 DNA단편을 가지고 있었으며, 재조합된 plasmid로부터 생산되는 pullulanase의 특성은 최적 활성 pH가 6.0이며, 효소의 pH안정성은 5-10이었다. 또한 형질 전환체로부터 생산되는 pullulanase의 localization,효소활성에 영향을 미치는 온도안정성 둥을 조사하였다.

• Korean Journal of Microbiology
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• v.18 no.1
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• pp.29-34
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• 1980

As preliminaries for the study of Plasmid pKM101 functions nad their interaction with the host DNA repair genes, seven mutants of pKM101, visualized on tetrazolium-galactose plates, deficient in their abitity to enhance mutagenesis were isolated and paritally characterizee. They all have altered functions not only for mutagenesis against MMS and 4-NQO but for the spontaneous reversion of host cell.

• Proceedings of the Botanical Society of Korea Conference
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• 1987.07a
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• pp.51-62
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• 1987

Higher plant transformation vector systems are mainly developed based on the natural biosystems which infecting higher plants. Two major groups attracting much of the research are Cauliflower mosaic virus and Agrobacterium tumefaciens. Cauliflower mosaic virus has a double stranded genome, and a portion of the genome can be substituted for a foreign DNA segment without loosing the ability of infection. A. tumefaciens carries a large plasmid. Ti plasmid whose portion can be substitute and trasferred into the plant chromosome.

• Korean Journal of Microbiology
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• v.35 no.3
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• pp.218-225
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• 1999

We isolated the ANRI fragment from Aspergillus nidulons that could autononlously replicate and enhance transformation efficiency about $10^4$ fold compared lo the integrative vector in Saccha,omgcer cerevisioe. In A. nidulans recombinant plasmid pLJ16-4.5 which carries the 4.5 kb EcoRI fragment of ANRI showed a 170-[old increase of transformation efficiency compared to the integrative vector pLJ16 and could be recovered from iransfonnants as an intact form. Estimated copy number of transforming plasmid pLJ16-4.5 was scored as 2 to 3 copies in transformed A. nidulans. Recoinbinant plasinid pILJ16-4.5 is inilotically unstable; being lost Irom 65% of aswual progeny of transformants on selective medium and 90% on complete medium. Southern analysis of transformant DNA showed that the pILJ16-4.5 is maintained in free form. The sequencing data showed that ANRl fragment was originated from mitochondiral DNA of A. nid~ilans and contained high AT content as much as 74.7%. One ARS consensus sequence (A/T)TTr4T(A/G)TTT(AiT). I I ARS-like sequence (agreement 10 of 11) and ABFl binding core consensus sequence (TCN7ACG). Also six gyrase binding core consensus sequence (YRTGNYNNY: y=C or T, R=A or G, N=A, G, C or T) of $\Phi$X174 and SV40 DNA and one b site (CACTTTACC) combining with gyrase in ColEl are shown. ANRl can be developed as a repl&ng plasinid for lransfoimation system in A. nirlulmis.

• Biomedical Science Letters
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• v.1 no.1
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• pp.55-72
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• 1995

Forty gentamicin-resistant isolates of Enterococcus faecalis were selected from various clinical materials, determined their antimicrobial susceptibility, and studied there R-plasmid characteristics and polypeptide patterns. All of the isolates were susceptible to vancomycin. The MICs($\mu$/ml) of antimicrobial agents to the isolates were as follows; the MIC of gentamicin was 128 and $\geq$2040, ampicillin 1 and 1, chlorarmphenicol 2 and 8, erythromycin 32 and 256, and vancomycin 1 and 2. E. faecalis HL-1 strain had 8 plasmid DNA elements, HL-2 and HL-3 strains had 6, HL-4 had 7, HL-5 had 4, and HL-6 had 5. The 51.7 Kb of gentamicin resistance plasmid DNA was conjugally transferred from two strains of E. faecalis HL-1 and HL-6 to S. aureus SK 982. The plasmid transfer frequency between S. aureus SK 982 and E. faecalis HL-1 or E. faecalis HL-6 was 6.3$\times10^{-4} and 3.7$\times10^{-5}$, respectively. Plasmid curing ratio after the treatment of ethidium bromide(10$\mu$/ml) to E. faecalis tarnsconjugants R-1 and R-6 were about 51% and 67%, respectively. The tetracycline gene was located in 2.15 Kb plasmid of E. faecalis HL-1, but it was not found in the E. faecalis HL-6 by Southern blot analyses. The antigenic components of E. faecalis HL-1, HL-6, R-1 and R-6 strains were analyzed by SDS-PAGE and immunoblotting. The E. faecalis strains had 7 to 16 polypeptide bands, however their major proteins were 97.8 and 26.8 Kd. At the Immunoblotting, 97.8, 95.8, 74.8, 63.5, 33.7 and 26.8 Kd polypeptides of the strains showed major antigenic activities with patient's sera infected intra-abdominally with an E. faecalis strain.

• Journal of Microbiology
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• v.37 no.2
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• pp.51-58
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• 1999

Using yeast, Saccharomyces cerevisiae, and the integrate vector system, we have isolated and characterized an autonomously replicating sequence (ARS) from Aspergillus nidulans. The DNA fragment, designated ANR1, is 5.0 kb in size and maintained free from the chromosome in S. cerevisiae. The YIplac211-ANR1 recombinant plasmid, which consists of sequences derived from the yeast integrative vector YIplac211 and 5.0 kb ANR1 fragment, showed a 104-fold enhancement in transformation efficiency over that found for YIplac211, and was easily recovered from the transformed yeast. Genetic analysis of transformants showed that YIplac21-ANR1 could be over 96% cured when cultured over 20 generations in complete medium and thus suggests that this sequence is mitotically unstable. In A. nidulans, recombinant plasmid PILJ16-4.5 which carries the 4.5 kb EcoRI fragment of ANR1 showed a 170-fold enhancement in transformation efficiency compared to that of the integrative vector PILJ16.