• Journal of Microbiology
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• v.34 no.2
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• pp.144-150
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• 1996

During growth of the genetically engineered E. coli CU103 in different media, extracellular DNAs released from the cells were studied. The extracellular DNAs released in the medium were concentrated by an thanol precipitation method and then quantified by a fluorescence method using Hoechst 33258. The released extracellular DNAs were also examined by gel electrophoresis and identified by Southern hybridization for the cloned pcbCD genes. The chromosomal DNAs and recombinant plasmid containing the cloned genes were observed to be released in an exponential growth phase. In Luria-Bertani (LB) broth and MM2-GLUCOSE, 210 and 69 ng/ml of DNAs were detected, respectively, after 3-4 days incubation at $30^{\circ}C$ and at pH 7.0. But the released DNAs were measured to be about 10-15 ng/ml in filtered river water (FW) and Tris-EDTA (TE). The at both $15^{\circ}C$ and $4^{\circ}C$, but the released DNAs were more easily degraded at the higher temperature. The extracellular DNAs were produced about 2 times more at pH 7.0 than at both pH 5.0 and pH 9.0 in MM2-glucose medium at $30^{\circ}C$. Therefore, the extracellular DNAs were found to be released actively from the cells during growth in liquid media.

• Korean Journal Plant Pathology
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• v.11 no.1
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• pp.73-79
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• 1995

Complementary DNAs (cDNAs) to the coat protein gene of an ordinary Korean strain of potato virus Y (PVY-OK) isolated from potato (cv. Superior) were synthesized and cloned into a plasmid pUC119 and sequenced. The RNA of the virus propagated in tobacco (Nicotinaa sylvestris) was extracted by the method of phenol extraction. The first strand of cDNAs to the coat protein penomic RNA of the virus was made by Moloney murine leukemia virus reverse transcriptase. The cDNA were synthesized and amplified by the method of polymerase chain reaction (PCR) using a pair of oligonucleotide primers. PVYCP3P and PVYCP3M. The size of cDNAs inserted in pUC119 plasmid was estimated as about 840 bp upon agarose gel electrophoresis. Double stranded cDNAs were transformed into the competent cell of E. coli JM109. Sequence analysis of cDNAs was conducted by the dideoxynucleotide chain termination method. Homology of cDNAs of the PVY-OK coat protein genomic RNA with those of PVY-O (Japan), PVY-T (Japan), PVY-TH (Japan), PVYN (The Netherlands),and PVYY (France) was represented as 97.3%, 88.9%, 89.3%, 89.6% and 98.5%, respectively. Homology at the amino acid level turned out to the be 97.4%, 92.5%, 92.9%, 92.9% and 98.5%, respectively.

• Proceedings of the KSAR Conference
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• 2004.06a
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• pp.209-209
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• 2004

This cDNAs were cloned with the method of the polymerase chain reaction (PCR) by sequences based on cloned rat LH/CG and FSH receptor cDNAs. A cDNAs of LHR and FSHR were transfected into the CHO cells. Several clonal cell lines were obtained expressing different numbers of cell surface receptors. (omitted)

• The Korean Journal of Food And Nutrition
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• v.8 no.4
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• pp.307-317
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• 1995

The purity of mtDNAs isolated from Archicitrus and Metacitrus leaves was higher in percoll density gradient centrifugation than differential and sucrose density gradient centrifugation. The most clear mtDNAs were obtained from mitochondria included in the Interface band of between 21% and 45% under isomotic, low viscosity conditions in the three step discontinuous percoll density gradient centrifugation. DNase treatment to the crude mitochondrlal suspension still more increased purity of mtDNA by the effective removal of the nuclear and chloroplast DNA and mtDNAs were appeared as a single band at middle position of tube by EtBr /cscl density gradient centrifugation. Agarose gel electrophoresis of mtDNAs resolved a single, broad band containing high molecular weight DNAs In all preparation. Yield of mtDNAs was about 110 and 2 ug Per 2009 in mature and immature leaves respectively. The mtDNA fragment patterns showed by EcoR I treatment were indistinguishable with respect to nom bet and position of bands in Archicitrus and Metacitrus. In the pattern of Hind E restriction, the Metacitrus displayed the unique band between 5.0 and 4.0kb, in addition to four fragments about 5.0, 2.4, 2.15, and 2.0kb, respectively, different from Archicitrus. Also the pattern of total mtDNAs fragment by the treatment of Pst I showed that the distinguishable fragment pat tern was not appeared in Archicitrus(C. iyo Tanaka), but about 6.0, 5.5, 5.0 and 2.Bkb fragments were appeared only in Metacitrus(C. junos Sieb). Therefore it was indicated that two species in intra-subgenus were identical each other, whereas considerable difference was revealed for inter-subgenus.

• Proceedings of the Polymer Society of Korea Conference
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• 2006.10a
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• pp.3-4
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• 2006

Natural DNAs in dry state, i.e., A-DNAs, when intercalated with low levels of stable organic free radicals or complexed with low levels of Au(III), are attracted at room temperature to commercial magnets, whereas those containing high levels of intercalators or Au(III) are not. This surprising observation is explained by the EPR spectra and SQUID measurement of magnetization of the modified DNAs. It is conjectured that A-DNAs are morphologically heterogeneous containing ordered and disordered regions. The ordered regions appear to strongly mediate magnetic interactions between spins through their ${\pi}_z$-stacked structures. When the modified DNAs are wet or hydrated, they behave diamagnetically.

• Korean Journal of Medicinal Crop Science
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• v.18 no.3
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• pp.186-190
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• 2010

The chromosome number was identified and fluorescence in situ hybridization(FISH) mapping of 5S and 45S rDNAs were conducted for C. minima and C. lanceolata in the genus Codonopsis from Jeju island. In this study, we have confirmed that the somatic metaphase chromosome number determined as 2n=2x=16 was the same as the findings from the previous studies. While the conventional staining method makes it rather difficult to distinguish satellite chromosomes due to high degree of variability, FISH analysis produced the exact number and location of 5S and 45S rDNAs. Both species in the genus Codonopsis have a pair of 5S rDNA and their gene loci were observed on chromosome 3. Although two pairs of 45S rDNAs (one on chromosome 1 and the other on chromosome 8) were identified in both species, the 45S rDNA signals on chromosome 8 in C. minima were significantly weaker than those on chromosome 1. In addition, the 45S rDNA signals on chromosome 1 in C. lanceolata showed that the chromosome is non-homologus. In this study, we have determined cytogenetic characteristics of C. minima and C. lanceolata according to their gene replication patterns.

• Journal of Genetic Medicine
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• v.3 no.1
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• pp.21-24
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• 1999

To study the X chromesome mosaicism in the cytogenetically pure 45,X Turner syndrome patients, we applied PCR technique using DNAs extracted from archived cytogenetic slides. We amplified the DNAs using nested primers targeted to a highly polymorphic short tandem repeat(STR) of the human androgen receptor gene(HUMARA) for the detection of X chromosome mosaicism. This assay is a very sensitive and useful method which can be applied to the DNAs extracted from archived cytogenetic slides to detect X mosaicism. We have tested 50 normal Korean females to determine whether the HUMARA locus is highly polymorphic among Koreans. 85% of Korean population showed heterozygosity in the HUMARA locus. We analysed the 24 DNAs extracted from archived slides of patients and abortuses with Turner syndrome in cytogenetic analysis. We observed the heterozygosities of 50% from pure 45,X patients, 83% from the patients with mosaic Turner syndrome and 8.3% from the abortuses of pure 45,X. Using the PCR technique of the HUMARA locus in the archived cytogenetic slides, we detected X chromosome mosaicism which could not be detected in cytogenetic analysis.

• Food Science of Animal Resources
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• v.43 no.1
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• pp.101-112
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• 2023

This study aimed to assess whether genomic DNA (gDNA) extracted from Pediococcus acidilactici inhibits Porphyromonas gingivalis lipopolysaccharide (LPS)-induced inflammatory responses in RAW 264.7 cells. Pretreatment with gDNA of P. acidilactici K10 or P. acidilactici HW01 for 15 h effectively inhibited P. gingivalis LPS-induced mRNA expression of interleukin (IL)-1β, IL-6, and monocyte chemoattractant protein (MCP)-1. Although both gDNAs did not dose-dependently inhibit P. gingivalis LPS-induced mRNA expression of IL-6 and MCP-1, they inhibited IL-1β mRNA expression in a dose-dependent manner. Moreover, pretreatment with both gDNAs inhibited the secretion of IL-1β, IL-6, and MCP-1. When RAW 264.7 cells were stimulated with P. gingivalis LPS alone, the phosphorylation of mitogen-activated protein kinases (MAPKs) was increased. However, the phosphorylation of MAPKs was reduced in the presence of gDNAs. Furthermore, both gDNAs restored IκBα degradation induced by P. gingivalis LPS, indicating that both gDNAs suppressed the activation of nuclear factor-κB (NF-κB). In summary, P. acidilactici gDNA could inhibit P. gingivalis LPS-induced inflammatory responses through the suppression of MAPKs and NF-κB, suggesting that P. acidilactici gDNA could be effective in preventing periodontitis.

• Proceedings of the Korean Vacuum Society Conference
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• 2016.02a
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• pp.140.1-140.1
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• 2016

We have measured DNA translocation through a nanocapillary functionalized with probe DNA. These DNA-functionalized nanocapillaries selectively facilitate the translocation of target ssDNAs that are complementary to the probe ssDNAs. In addition, translocation of the complementary target ssDNA exhibits two tendencies to translocation speed, such as fast and slow translocation, whereas that of non-complementary target ssDNA yields only one tendency, fast translocation. These observations suggest that the complementary and non-complementary target ssDNAs may be discriminated due to different interaction strengths between target and probe ssDNAs. The temperature dependence measurements of DNA translocation show that slow translocation events are ascribed to the complementary interaction between probe and target ssDNA. This confirms that their dwell time is dependent on the base-pair binding strength. These results demonstrate that mere single-base different target DNA can be selectively detectable by using the probe DNA-functionalized nanocapillaries.

• Journal of Plant Biology
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• v.39 no.3
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• pp.189-195
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• 1996

The major cuticular components have been shown to be synthesized in the epidermis. Therefore, cloning of epidermis-specific genes could yield information to be used to isolate and characterize the enzymes involved in the cuticle biosynthesis. A subtractive cDNA library was prepared from Senecio odorus in which epidermis-specific cDNAs were enriched. Differential screening of the library using epidermal and non-epidermal probes revealed two cDNAs. One of them designated epi425 was identified, based on the sequence homology, as a member of a new class in the LTP gene family and the other clone designated epi23 as a gene encoding an aldehyde decarbonylase. Northern blot analyses showed that epi425 and epi23 cDNAs hybridized with a transcript of about 600 and 2, 100 nucleotides, respectively, from the epidermis but not from the non-epidermal tissues. Further characterization of these clones will provide more information on the mechanism of the cuticle biosynthesis.