• Microbiology and Biotechnology Letters
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• v.28 no.6
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• pp.316-321
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• 2000

Role of enterotoxin from Salmonella in pathogenesis is not know. Enterotoxin gene from Salmonella typhimurium(stn) encodes a 29kDa toxin that has no homology to any other known enterotoxins. Expression of stn is enthanced upon contact with epithelial cell but not all strains having the stn gene express Stn, Based on PCR analysis, we found that all 36 clinical strains of Salmonella isolated in Korea tested carried the stn gene. To understand the trgulation of the stn transcription, the expression of stn was studies in vitro. RNA polymerase was purified by polymin P fraction-ation, DNA-agarose affinity chromatography, and Mono-Q ion exchange chromatography from Salmonella. The expression of stn was inhibited by cAMP·CRP complex by about 50%.

• Journal of Oral Medicine and Pain
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• v.19 no.2
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• pp.205-219
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• 1994

Cigarette butts from 5 smokers were gathered and then, placed in room temperature for 1, 3, 5, 7, 15 days. The possible use of the cigarette butts for individual identification was evaluated in sex determination, amplification of D1S80 locus, polymorphisms of HLA-DQA1 gene from the extracted DNA. 1. DNA extraction was possible in cigarette butts weree left in room temperature for 15days, so it can be applicatable to individual identification by polymerase chain reaction(PCR). 2. Amplification of X-Y homologous amelogenin gene by PCR made it possible to identify the sex in saliva stains (cigarette butts). 3. Amplification of D1S80 locus can be acquired from adding the boving serum albumin and hot start PCR procedures from forensic samples such as saliva stains (cigarette butts), so the AMP-FLPs examining is possible. 4. Genotype could be determined simply and rapidly using Amplitype$TM$ HLA-DQ$\alpha$ forensic kit in examining the HLA-DQA1 gene. From the investigation, DNA extraction, sex determination, amplification of D1S80 locus, polymorphisms of HLA-DQA1 gene was successfully done even though the cigarette butts were left for 15 days at room temperature. Therefore cigarette butts are highly reliable and applicatable as molecular biologic samples for individual identification.

• Journal of Microbiology and Biotechnology
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• v.17 no.7
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• pp.1090-1097
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• 2007

Genomic analysis of Thermococcus sp. NA1 revealed the presence of a 3,927-base-pair (bp) family B-type DNA polymerase gene, TNA1_pol. TNA1_pol, without its intein, was overexpressed in Escherichia coli, purified using metal affinity chromatography, and characterized. TNA1_pol activity was optimal at pH 7.5 and $75^{\circ}C$. TNA1_pol was highly thermostable, with a half-life of 3.5h at $100^{\circ}C$ and 12.5h at $95^{\circ}C$. Polymerase chain reaction parameters of TNA1_pol such as error-rate, processivity, and extension rate were measured in comparison with rTaq, Pfu, and KOD DNA polymerases. TNA1_pol averaged one incorrect bp every 4.45 kilobases (kb), and had a processivity of 150 nucleotides (nt) and an extension rate of 60 bases/s. Thus, TNA1_pol has a much faster elongation rate than Pfu DNA polymerase with 7-fold higher fidelity than that of rTaq.

• Applied Biological Chemistry
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• v.40 no.4
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• pp.271-276
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• 1997

We have prepared several chimeric constructs containing the bacteriophage T7 RNA polymerase gene under control of the wound-inducible potato proteinase inhibitor II (pin2) promoter and have transformed Nicotiana tabacum plants with these constructs. Southern blot analyses indicate that either one or two copies of the gene constructs are present in the transgenic plants. Northern blot analyses indicate that mRNA encoding T7 RNA polymerase is expressed in a wound-inducible manner. We purified T7 RNA polymerase and prepared antiserum. This antiserum was used for Western blot analyses to demonstrate that a protein which is cross reactive with T7 RNA polymerase is produced. The molecular mass of this protein is 80 kDa, a size which is consistant with the nicked form of the polymerase as is often seen when expressed in E. coli. RNA polymerase assays were used to indicate that the nicked form of T7 RNA polymerase is active and capable of incorporating labeled nucleotides into transcripts in vitro. Analysis of transgenic plants did indeed show that wound-inducible activation of the T7 RNA polymerase permits the establishment of a genetic system to overexpress genes in plants using T7 RNA polymerase(Received March 20, 1997; accepted May 2, 1997)

• Journal of the Korea Institute of Information and Communication Engineering
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• v.17 no.4
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• pp.1005-1009
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• 2013

Using DNA sequencing method, we analyzed mutations of rpoB (RNA polymerase beta subunit) rifampin-resistant Mycobaterium tuberculosis strains which were identified by conventional test at Masan National Hospital and The Korean Institute of Tuberculosis. Though it has been reported different mutations of rpoB region of rifampin-resistant M. tuberculosis strains in the south of Korea, it is not confirmed whether these mutations of rpoB region actually express rifampin resistance through experiment. We confirmed experimentally these mutations of rpoB region of M. tuberculosis strains induced rifampin-resistance through ampified rpoB by polymerase chain reaction (PCR) and cloning of mutant rpoB into rifampin sensitive-M. tuberculosis strain.

• Journal of fish pathology
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• v.5 no.2
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• pp.143-152
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• 1992

Metallothionein is an essential and common protein to regulate the intracellular concentration of heavy metals, which exist in most organisms from bacteria to vertebrates. Although the detailed function of metallothianein has not been fully identified until yet, it may be involoved in the cellular protection against the heavy metal toxicity and in the global regulation of several other genes and the expression of metalloproteins. We have cloned the full cDNA clone of metallothionein gene in Channel Catfish by Reverse Transcriptase-Polymerase Chain Reaction(RT-PCR) starting from poly(A)-containing mRNAs. All PCR fragments have been subcloned into EcoRV site of pBluescript SK+ and dT-tailed at Smal site of pUC19, then PCR products are recovered by the double digestion of recombinant plasmids wiht EcoRI and HindIII, which are adjacent to EcoRV site in multicloning sites or by rapid PCR screening. The nucleotide sequence analysis of pMT150(one of the PCR clones) showed high homology with several other piscine metallothionein cDNA genes.

• Korean Journal of Microbiology
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• v.30 no.6
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• pp.456-459
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• 1992

The genes of Halohacteria. gvpD and gvpE. take part in formation of gas vesicle. These mRNA cause a lot of experimental prohlems due to its eharacteristic instahility in the analysis of transcripts. This study allowed easy cloning and sequencing of RNA hy substituting a stable complementary DNA for the mRNA of the genes for an analysis. The weak 111 RNA was reverse transcribed to DNA using reverse transcriptase. and was amplified using PCR method. The transcripts confirmed in this ~,tudy have not heen round in the northern hybridization covering almost all ranges of ORF of the gene. gvpD.

• Journal of Life Science
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• v.21 no.5
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• pp.626-630
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• 2011

In October 2008, a pair of Crested ibis Nipponia nippon, an endangered avian species in the world, was donated to Korea from China. They have since been the subject of a successful program to incubate chicks for the first time in South Korea. This study was carried out to determine the sex of chicks from the Crested ibis through polymerase chain reaction (PCR) using the sex-related gene and the chromodomain helicase DNA binding protein (CHD) gene. The result of the CHD gene, which was used with a single set of primers and a restriction enzyme treatment after the PCR process, was more accurate in identifying the gender of the Crested ibis. In addition, we compared the CHD gene sequences with the previously reported sequences and found 1~2 different bases between females (CI2, CI4, CI5, and CI6) than in studies previously reporting female sequences.

• Journal of Microbiology
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• v.34 no.3
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• pp.229-235
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• 1996

Microgram quantities of DNA per gram soil were recovered with SDS- based and freeze-and thaw procedures. The average DNA fragment size was > 23 Kb. This method generated minimal shearing of extracted DNA. However, the DNA extracts still contained considerable amounts of humic impurities sufficient to inhibit PCR. Several approaches were used to reduce the interferences with the PCR (use of CTAF in extraction step, Elutip-d column purification, addition of BSA to PCR buffer) to accomplish PCR with DNA extract as a template. Most of the DNA extracts were not digested completely by restriction endonuclease, and CTAB-TREATED ane Elutip-d column purified DNA extracts were partially digested. Regarding as restriction enzyme digestion, all PCRs failed to amplify 16S rRNA gene fragments in the DNA extracts. In the case of DNA extracts only where BSA was added to PCR buffer, PCR was successfully conducted whether the DNA extracts were treated with CTAB or purified with columns. However, these two treatments were indispensable for humic impurity-rich DNA extracts to generate the PCR-compatible DNA samples. Direct extraction of DNA, coupled with these procedures to remove and relieve interferences by humic impurities and followed by the PCR, can be rapid and simple method for molecular microbiological study on soil microorganisms.

• Korean journal of applied entomology
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• v.35 no.4
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• pp.315-320
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• 1996

The effects of 2-arnino-3-methyIimidazo[4,5-fq]u inoline (IQ), 2-amino-6dimethyl-dipyrido[l,2-a;3',2'-d] imidazole (Glu-P-1) and aflatoxin B1 (AFBI) on the mitotic recombinations and somatic chromosome mutations were investigated using the transgenic Drosophila bearing a chimeric gene consisting of a promoter region of Drosophila actin 5C gene and rat DNA polymerase $. For investigating mitotic recombinations and the somatic chromosome mutations, the heterozygous (mwhl+) strain possessing or lacking transgene pol P was used. The spontaneous frequency of small mwh spots, due to deletion or nondisjunction etc., in the non-transgenic w strain and the transgenic plpol $1-130 strain was 0.351 and 0.606, respectively. The spontaneous frequency (0.063) of large mwh spots, arising mostly from somatic recombination between the centromere and the locus mwh, in the transgenic plpol $1-130 strain, was about three times higher than that (0.021) of the non-transgenic w strain. The mutant clone frequencies of two types induced by two heterocyclic mines (IQ and Glu-P-1) and AFBl in the transformant pbol PI-130 were two or three times higher than those in the host strain w. These mean that rat DNA polymerase P participates at least in the somatic chromosome mutations and mitotic recombination processes. And the present results suggest that the transgenic Drosophl!~ used in this study can be used as a hypersensitive, in vivo short-term assaying system for various environmental mutagens.