• Korean Journal of Veterinary Research
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• v.34 no.4
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• pp.759-768
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• 1994

E coli strains isolated from pigs were investigated with respect to antimicrobial resistances and prevalence of R-plasmids. Also determined were properties of R-plasmids by plasmid conjugation, curing and southern hybridization using gene probes. All of 400 E coli strains were resistant to CL and SU, and 0.3% to 96.8% of the strains were resistant to most antimicrobials such as TC, PG, AM, SM, CP, GM, EM, NM, etc, while all strains were sensitive to AK. All strains were also multiply resistant to three to twelve antimicrobials. The resistances to PG, SM, TC, AM, CP, SU and ST were transferable and supposed to be mediated by R-plasmids which were opportunistic for transposition into chromosome. Plasmids bigger in size than chromosomal DNA were considered as R-plasmids and most plasmids in small size (<4Kb) proved as cryptic plasmids or nonconjugative R-plasmids. In a strain(No 99), AM resistant property was determined from both chromosomal DNA and R-plasmid DNA which is bigger in size than chromosome.

• Journal of Animal Science and Technology
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• v.44 no.1
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• pp.13-22
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• 2002

To identify the differentially expressed genes at growth stage of Hanwoo, we constructed the subtractive cDNA library from loin mRNA of 12- and 24-month old Hanwoo by PCR-based subtraction. The fourteen genes were confirmed by sequencing and reverse northern blot analysis, and they were selected as candidate of putative genes differentially expressed at the growth stage of Hanwoo. Three subtracted cDNA fragments that expressed specific signal to cDNA probe for 6-month-old loin of Hanwoo were highly homologous to those of the genes encoding EPV 20, Ca2＋ATPase, and TCTP, respectively. The nine cDNA clones showed intense signal to cDNA probe from 12-month-old loin of Hanwoo, and highly homologus to those of genes encoding VCP, HSP 70, aldolase A, MSSK1, GM-2 activator protein, ryanodine receptor, acidic ribosomal phosphoprotein p1, ADP/ATP translocase, and UCP 2, respectively. Two subtracted cDNA clones that expressed specific signal to cDNA probes for 12- and 24-month-old loin of Hanwoo were detected. One of them was highly homologus to the gene encoding ferrochelatase and the other was highly homologus to the gene encoding ADRP.

• BMB Reports
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• v.37 no.3
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• pp.356-361
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• 2004

To develop a simplified method that can rapidly prepare DNA microarray probes in a massive scale, a lambda phage genomic DNA-fragments library was constructed for the microarray-probes collection. Four methods of DNA band recovery from the first PCR products were tested and compared. The DNA microarray probes were collected by a novel method of nested PCR that was mediated by gel isolation of the first PCR products. This method was named GIN-PCR. The probes that were prepared by this GIN-PCR technique were used as subjects to fabricate a DNA microarray. The results showed that a wooden toothpick was superior to the other 3 methods, since this technique can steadily transfer the DNA bands as the template of the second PCR after the first PCR. A group of probes were successfully collected and DNA microarrays were constructed using these probes. Hybridization results demonstrated that this technique of DNA recovery and probe preparation was rapid, efficient, and effective. We developed a cost-effective and less labor-intensive method for DNA microarray probe preparation by nested PCR that is mediated by wooden toothpick transfer of the DNA bands in the gel after electrophoresis.

• The Korean Journal of Mycology
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• v.25 no.1 s.80
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• pp.1-5
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• 1997

The cDNA encoding ${\beta}-tubulin$ of Pleurotus sajor-caju was isolated using an internal gene segment probe amplified by polymerase chain reaction (PCR) of genomic DNA and by cDNA library screening. The cDNA was consisted of 1560 nucleotides(nt), including a 5'-untranslation region (UTR) of 27nt, an open reading frame (ORF) of 1341nt, and a 3'-UTR of 191nt. The ORF encoded a protein of 446 amino acids(aa), which shows over 80% homology with ${\beta}-tubulins$ of other filamentous fungi. Southern hybridization analysis showed that there were two isotypes of ${\beta}-tubulin$ genes in P. sajor-caju. Through sequence analysis we found that ${\beta}-tubulin$ had a unusual $Cys^{165}$ residue, which might be a significant factor for the insensitivity of fungi to fungicide benomyl.

• Korean Chemical Engineering Research
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• v.48 no.2
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• pp.147-156
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• 2010

There are four key factors for gas-phase biofilters; biocatalysts(microorganisms), packing materials, design/operating techniques, and diagnosis/management techniques. Biofilter performance is significantly affected by microbial community structures as well as loading conditions. The microbial studies on biofilters are mostly performed on basis of culture-dependent methods. Recently, advanced methods have been proposed to characterize the microbial community structure in environmental samples. In this study, the physiological, biochemical and molecular methods for profiling microbial communities are reviewed, and their applicability to biofilters is discussed. Community-level physiological profile is based on the utilization capability of carbon substrate by heterotrophic community in environmental samples. Phospholipid fatty acid analysis method is based on the variability of fatty acids present in cell membranes of different microorganisms. Molecular methods using DNA directly extracted from environmental samples can be divided into "partial community DNA analysis" and "whole community DNA analysis" approaches. The former approaches consist in the analysis of PCR-amplified sequence, the genes of ribosomal operon are the most commonly used sequences. These methods include PCR fragment cloning and genetic fingerprinting such as denaturing gradient gel electrophoresis, terminal-restriction fragment length polymorphism, ribosomal intergenic spacer analysis, and random amplified polymorphic DNA. The whole community DNA analysis methods are total genomic cross-DNA hybridization, thermal denaturation and reassociation of whole extracted DNA and extracted whole DNA fractionation using density gradient.

• Microbiology and Biotechnology Letters
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• v.31 no.2
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• pp.205-209
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• 2003

Recently, we introduced a new method for rapid screening of bacterial species- or subspecies-specific DNA probes, named “inverted dot blot hybridization screening method”. We then applied this method to develop species- or strain- specific DNA probes for Prevotella intermedia and Prevotella nigrescens. In those studies, among 96 candidate DNA probes which were screened by the new method, 5 probes were confirmed as being putatively strain-specific : 3 probes for P. nigrescens 9336 (ATCC 33563), one for each p. intermedia ATCC 25611 and one for P. nigrescens G8-9K-3 (ATCC 49046). In the present study, we evaluated by Southern blot analysis a DNA probe Pi29-L, one of the 96 candidate probes described above, whether it is specific for the strain ATCC 25611 off. intermedia. Our data show that the probe Pi29-L is potentially P. intermedia ATCC 25611-specific, which can be useful for the detection and identification of the strain, particularly in maintenance of the strain.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.57 no.2
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• pp.320-326
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• 2008

In this paper, we propose a new algorithm emulating the DNA characteristics for noise-tolerant pattern matching problem on digital system. The digital pattern matching becomes core technology in various fields, such as, robot vision, remote sensing, character recognition, and medical diagnosis in particular. As the properties of natural DNA strands allow hybridization with a certain portion of incompatible base pairs, DNA-inspired data structure and computation technique can be adopted to bio-signal pattern classification problems which often contain imprecise data patterns. The key feature of noise-tolerance of DNA computing comes from control of reaction temperature. Our hardware system mimics such property to diagnose cardiovascular disease and results superior classification performance over existing supervised learning pattern matching algorithms. The hardware design employing parallel architecture is also very efficient in time and area.

• Animal cells and systems
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• v.1 no.4
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• pp.629-635
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• 1997

Previously we reported the migration and rearrangement of a chloroplast gene cluster into mitochondria. The exact genomic locations of the clusters, modes of the gene rearrangement and mechanisms of the interorganellar migration of the clusters have yet to be understood. The detailed analysis needs to include a larger region of DNA surrounding each cluster. To study DNA rearrangement and migration in more detail a cosmid library was constructed using the total rice genomic DNA including nuclear, chloroplast and mitochondrial DNA. From this cosmid library, a sub-library was obtained by selecting the clones hybridized to various regions of chloroplast DNA. According to the hybridization pattern 136 clones from the sub-library were classified into 29 groups. Detailed analysis of these clones revealed that in addition to authentic chloroplast DNA, the clones contain its homologs resulted from rearrangement and mutation. We analyzed two clones in detail, which contain different rp12 homologs resulted from rearrangement and/or migration, respectively.

• Fisheries and Aquatic Sciences
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• v.21 no.5
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• pp.11.1-11.8
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• 2018

Interspecific hybridization experiments were conducted between the common seahorse Hippocampus kuda (male) and the slender seahorse H. reidi (female) during artificial rearing to develop a new aquarium fish with unique polyandrous mating. Molecular analysis via mitochondrial DNA (mtDNA) cytochrome b and nuclear DNA (ncDNA) ribosomal protein S7 gene supported the hybridization between the two species, and the hybrid also showed morphological characteristics of both species. Juveniles of H. kuda have dense melanophores on the whole body or only on the trunk and tail, whereas juveniles of H. reidi have thin melanophores on the whole body or present in stripes only along their prominent trunk and tail rings. However, all the hybrid juveniles had dense melanophores only on the tail, with the striped trunk rings, thus showing an intermediate pattern, and these patterns were limited to the fairly early stage of development (1-10 days old). In contrast, the two eye spines in the hybrid were apparent after 9 days old, which were not inherited from H. kuda (one eye spine), but from H. reidi (two eye spines). According to LOESS (local regression) analysis, the growth rate increased between 20 and 25 days, and the hybrids grew faster than H. kuda when they entered the explosive second phase of growth between 25 and 45 days for all the seahorses. This study highlights the hybridization between H. kuda and H. reidi may contribute to the improved taxonomic information of young seahorses.

• Journal of Life Science
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• v.16 no.1
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• pp.126-130
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• 2006

The present study intends to characterize the DNA damage-inducible responses in yeast. The fission yeast, Schizosaccharomyces pombe was used in this study as a model system for higher eukaryotes. To study UV-inducible responses in S. pombe, five UV-inducible cDNA clones were isolated from S. pombe by using subtration hybridization method. To investigate the expression of isolated genes, UVI-155, the cellular levels of the transcripts were determined by Northern blot analysis after UV-irradiation. The transcripts of isolated gene (UVI-155) increased rapidly and reached maximum accumulation after UV-irradiation. Compared to the message levels of control, the levels of maximal increase were approximately 5 fold to UV-irradiation. In order to investigation whether the increase of UVI-l55 trascripts was a specific results of UV-irradiation, UVI-155 transcript levels were examined after treating the cells to mthylmethane sulfonate (MMS). The transcripts of UVI-155 were not induced by treatment of $0.25\%$ MMS. These results implied that the effects of damaging agents are complex and different regulatory pathways exist for the induction of these genes. To characterize the UVI-155 gene, gene deletion experiments were analyzed. The deleted strain was not well grown. This result indicated that the UVI-155 gene is essential for cell viability.