• Environmental Mutagens and Carcinogens
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• v.22 no.3
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• pp.137-141
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• 2002

The SNF2/SW12 family comprises proteins from a variety of species with in vivo functions, such as transcriptional regulation, maintenance of chromosome stability during mitosis, and various types of DNA repair. This study was shown the characterization of hrp2+ gene which was isolated by PCR amplification using the conserved domain of SNF2 motifs. Sequence analysis of hrp2+ gene showed striking evolutionary conservation among the SNF2 family of proteins. The transcript of hrp2+ gene was found to be a 4.7 kb as identified by Northern hybridization. In addition, to determine the transcription initiation site of hrp2+ gene, primer extension analysis was performed. This result showed the band of 64 bp. The transcriptional start point was mapped to a position of 47 base pair from the first ATG codon of translational initiation codon. In order to investigate the inducibility of hrp2+ gene, transcript levels were examined after treating the cells to various DNA damaging agents. The transcripts of hrp2+ were induced by UV-irradiation. But the transcripts were not induced by treatment of 0.25% Methylmethane sulfonate (MMS). These results implied that the effects of damaging agents are complex and different regulatory pathways exist for the induction of this gene.

• Journal of Microbiology
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• v.37 no.3
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• pp.168-174
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• 1999

Escherichia coli O157 is an important pathogenic organism which causes diarrhea, haemorrhagic colitis, and haemolytic ureamic syndrome (HUS) in human. E. coli O157 KNIH317 was isolated form patients suffering with HUS in Korea. We designed a primer set for cloning shiga-like toxin (slt) gene. The amplified PCR product was used to Southern and colony hybridization as a probe. As a result, we cloned 4.5-kb KpnI fragment containing the slt gene encoding shiga-like toxin from chromosomal DNA of E. coli O157 KNIH317. This recombinant plasmid was named pOVT45. E. coli XL1-Blue harboring pOVT45 showed cytotoxicity in Vero cells. We sequenced the slt gene of this strain. The A-subunit gene of the slt was composed of 960 base pairs with ATG initiation codon and TAA terminationcodon. The B-subunit was composed of 270 base paris with ATG initiation codon and TGA termination codon. Nucleotide sequence comparison of the slt gene exhibited 100%, 98.4%, 93.7%, and 93.7% identity with that of shiga-like toxin type II (sltII) of E. coli bacteriophage 933W, variant slt of E. coli, slt of E. coli, and variant sltII of E. coli, respectively. From these results, it was concluded that the cloned slt gene belongs to SltII family and that the strain used in this study may be a lysogeny of E. coli bcteriphage 933W.

• The Korean Journal of Physiology and Pharmacology
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• v.1 no.2
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• pp.195-200
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• 1997

Water transport in highly-permeable membranes is facilitated by some specialized pathways, which are called aquaporins (AQP). AQP1 (AQP-CHIP) is the first recognized aquaporin identified from red cells and renal proximal tubules. Up until now 4 other aquaporin homologs have been reported. Each aquaporin has its unique tissue distribution and regulatory mechanims. To elucidate molecular mechanisms for their transcription regulation and tissue-specific expression isolation of aquaporin genes is required. To clone promoters of the AQP family mouse genomic library was screened by the 1st exon-specific probe of AQP4, and 5 different plaques were positively hybridized. Phage DNAs were purified and characterized by restriction mapping and sequencing. One of them is the mouse AQP-CD gene. The gene was consisted of 4 exons and the exon-intron boundaries of mouse AQP-CD gene were identified at identical positions in other related genes. The 5'-flanking region of AQP-CD gene contains one classic TATA box, a GATA consensus sequence, an E-box and a cyclic AMP-responsive element. The cloning of the mouse AQP-CD gene, of which product is expressed in the collecting duct and is responsible for antidiuresis by vasopressin, will contribute to understand the molecular mechanisms of tissue-specific expression and regulation of AQP-CD gene under various conditions.

• Applied Biological Chemistry
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• v.41 no.2
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• pp.125-129
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• 1998

Xanthomonas sp. isolated from soil exhibited cell wall lytic activity of Candida albicans and secreted chitinase in chitin media. Especially, the chitinase activity was induced by chitin and reached a maximum level at 3 days culture in chitin media. We constructed genomic library of Xanthomonas sp. using cosmid vector in E. coli. Oligonucleotide probe was synthesized from the consensus sequence corresponding to chitinase active site, which was derived from the comparison of amino acid sequences of bacterial chitinase genes. Using this oligonucleotide probe, we screened the genomic library. By restriction enzyme mapping of the positive clones, we identified 4 independent clones which may contain the chitinase gene. One of the clones, named pXCH1 (1.2 kb insert), was further analyzed. Northern blot analysis indicated that is transcripts, 1 kb and 0.8 kb, were induced by chitin. When the cloned gene was induced by IPTG in E.coli cell, chitinase activity which was secreted onto culture media was not observed. However, when the cell was disrupted by using sonicator and then centrifuged, the supernatant exhibited chitinase activity. SDS-PAGE of the supernatant indicated that about 35 kDa protein was induced by IPTG. From these results, it was concluded that the cloned DNA was one of the chitinase genes of Xanthomonas sp.

• Applied Biological Chemistry
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• v.40 no.6
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• pp.495-500
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• 1997

To isolate a gene for cyclodextrin glycosyltransferase (CGTase) from alkalophilic Bacillus sp. E1, polymerase chain reaction (PCR) amplification was carried out. Direct molecular cloning of 1.2 kbp fragment and partial nucleotide sequence analysis of the PCR amplified clone, pH12, showed close homology with CGTases from Bacillus species. To investigate the genomic structure of the gene, Southern blot analysis of genomic DNA was carried out with the clone pH12 as a molecular probe. It showed that 5.3 kbp XbaI fragment was hybridized with the probe pH12. To isolate a genomic clone, genomic DNA library was constructed and a genomic clone for CGTase, pCGTE1, was isolated. Nucleotide sequence analysis of the clone pCGTE1 revealed that BCGTE1 contained 2,109 bp open reading frame encoding a polypeptide of 703 amino acids and showed over 94.3% amino acid sequence homology with CGTase of ${\beta}-cyclodextrin$ producer, Bacillus sp. KC201.(Received October 7, 1997; accepted October 20, 1997)

• Korean Journal of Veterinary Research
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• v.55 no.2
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• pp.105-110
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• 2015

A real-time PCR assay using hybridization probe (HybProbe) has been developed to detect Brucella (B.) melitensis strains. The primer and HybProbe sets were designed based on the gap gene of chromosome I with a specific single nucleotide polymorphism of B. melitensis. Specificity of the assay was confirmed by comparison to reference Brucella species and other related strains. In the melting curve analysis, B. melitensis generated a peak at $67^{\circ}C$ unlike those for other Brucella species observed at $61^{\circ}C$. Sensitivity of the assay for B. melitensis ranged from 20 ng to 200 fg of genomic DNA. The ability to identify 94 Mongolian B. melitensis isolates using the real-time PCR assay was identical to that of classical biotyping methods and differential multiplex PCR. These data showed that this new molecular technique is a simple and quick method for detecting B. melitensis, which will be important for the control and prevention of brucellosis.

• Korean Journal of Veterinary Service
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• v.35 no.3
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• pp.215-222
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• 2012

Species-specific $TaqMan^{(R)}$ probe-based real-time PCR assays were developed for detection of beef, pork, chicken, duck, goose and turkey. The primer and probe sets used in this study were designed to be complementary to fibroblast growth factor (FGF) for cattle and pig, mitochondrial NADH dehydrogenase (ND) subunit 3 and ND2 for chicken and duck, 12S rRNA for goose and turkey, respectively. As internal positive control we used conserved region in the ribosomal 18S RNA gene to ensure the accuracy of the detection of target DNA by real-time PCR. We confirmed that real-time PCR assays with the primer and probe sets were positive for cattle, pig and chicken intended target animal species with no cross-reactivity with other non-target animal species. Only >50 ng DNA of beef show cross-reactivity in the determination of duck. Using species-specific primer and probe sets, it was possible to detect amounts of 0.1 ng DNA of cattle and pig, 1.0 pg DNA of chicken, duck and turkey, and 0.1 pg DNA of goose for raw samples, respectively. The detection limits were 0.1 ng DNA of cattle, 1.0 ng DNA of pig and 1.0 pg DNA of chicken for DNA mixtures (beef, pork and chicken) extracted from heat-treated ($121^{\circ}C$/5 min) meat samples. In conclusion, it can be suggested that the $TaqMan^{(R)}$ probe-based assay developed in this study might be a rapid and specific method for the identification of meat species in raw or cooked meat products.

• Development and Reproduction
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• v.7 no.1
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• pp.41-48
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• 2003

This report aimed at investigating the differential gene expressions of the adhesion receptors between ovariectomized (OVX) and estrus stage rat uteri (OVX vs. estrus pair) using the cDNA expression away analysis. In addition, this report aimed at confirming of the differential gene expressions of the adhesion receptors between OVX and progesterone (P$_4$) injected OVX rat uteri (OVX vs. OVX+P$_4$ pair). RNA samples were extracted from the uterus and reverse-transcribed in the presence of [$\alpha$$^{32}$ P]-dATP. Membrane sets of Rat Atlas array 1.2 II (Clontech) were hybridized with CDNA probe sets. RT-PCR was employed to validate the relative gene expression patterns obtained by the cDNA array. The results were well consistent to cDNA array analysis data except the fold changes of gene expression. Among a total of 1176 cDNAs, 5 genes of adhesion receotor including embigin protein, activated leukocyte cell adhesion molecule, afadin, neuroligin 2, semaphorin Z showed significant (more than 2-fold) changes in the OVX vs. late estrus pair. All of these genes were up regulated in estrus stage than OVX rat uterus. In the OVX vs. OVX+P$_4$ pair, 4 genes including osteonectin, afadin, neuroligin 2, semaphorin Z showed significant changes. All of these genes were also up regulated in OVX+P$_4$ injected rat uterus than OVX control. Three genes including afadin, neuroligin 2, semaphorin Z which were up regulated in estrus and OVX+P$_4$ injected rat uteri of both experimental pairs than OVX rat uteri. These genes seem to be under the control of P$_4$.

• Korean Journal of Plant Tissue Culture
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• v.22 no.6
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• pp.329-334
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• 1995

Transformation system of rolC gene, dwarf gene in Lycium chinenese Mill. established by using system. Pin-punctured leaves induced numerous adventious buds in abaxial side when cultured on 3/2 MS medium containing 2.0 mg/L zeatin. Survival rate and shoot regeneration frequency of leaf explants decreased as kanamycin sulfate level increased. Shoot buds were not regenerated on 3/2 MS medium containing 10 mg/L kanamycin sulfate and 2.0 mg/L zeaein. Of the level tested, 10 mg/L of kanamycin sulfate was optimum in selection of kanamycin sulfate resistant plant. Co-culture time of bacteria and leaf explants was affected at the frequency of shoot regeneration and survival of leaf explants. Leaf explants co-cultivated during above 48hr severely decreased survival rate and shooting rate. Best result on survival rate and shooting rate were obtained when exposed for 24 h. 80 explants of 105 leaf explants survived on 3/2 MS medium containing 2.0 mg/L zeatin and 10 mg/L kanamycin sulfate, and 15 shoots was regenerated on the same medium. To select kanamycin sulfate resistant plant, regenerate as cultured on 3/2 MS medium containing 10 mg/L kanamycin sulfate, and obtained 5 kanamycin resistant plants. Southern blot analysis conformed that the rolC gene was incorporated into the genomic DNA of kanamycin resistant plants.

• Proceedings of the Microbiological Society of Korea Conference
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• 2007.05a
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• pp.83-85
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• 2007

Deep-sea bacteria are adapted to extreme environments, such as high pressures and cold temperatures. We have isolated many piezophiles which grow well even under high pressures from deep-sea sediment. Shewanella violacea DSS12 and Moritella japonica DSK1 have the ability to grow at up to 70 MPa, and those bacteria have unique mechanisms of gene expression in response to high pressure conditions. The combination of gene expression systems in piezophiles, like the high pressure-dependent promoters and GFP reporter gene, may reveal highly fluorescent cells when exposed to high hydrostatic pressure conditions. It is predicted that a novel bio-sensing system can be made to probe high pressure environments using living bacteria. First, gene transformation into our piezophiles, strains DSS12 and DSK1, were examined. Eschericha coli S17-1 was used for bacterial conjugation with those piezophiles. As a result, the broad host range vector, pKT231, and the shuttle vector, pTH10, were successfully introduced to DSS12 and DSK1, respectively. Next, The pressure regulated promoters from DSS12 and DSK1 were cloned into proper vectors and combined with GFP as a reporter gene downstream of each promoter. The transformants of DSK1 and DSS12 with the recombinant pTH10 and pKT231 plasmid, which has cadA and glnA promoters (each of them is a pressure regulated promoter from DSK1 and DSS12, respectively) and GFP, were grown under high pressure and gene expression of GFP promoted by 50 MPa pressure was confirmed. This is a critical point to create a pressure-sensing bacteria, as the "High Pressure Glow Cells", which will indicate the level of environmental pressure using fluorescence of GFP as a reporter gene.