• 미생물학회지
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• 제43권2호
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• pp.91-99
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• 2007

인간면역결핍바이러스(Human immunodeficiency virus; HIV) 진단을 위한 다중, 초고속실시간 PCR법을 개발하였다. 검출대상의 DNA 염기서열은 env 유전자를 기반으로 설계되었으며, 각기 HIV-1 특이 495염기(gi_1184090) 및 HIV-2 특이 294염기(gi_1332355)의 DNA를 안정상의 이유로 PCR을 이용한 유전자합성법으로 제작하여 사용하였다. 초고속 실시간 PCR은, PCR의 회전 중 각 단계별 설정시간을 극단적으로 축소하여, $1\;{\mu}l$의 PCR 용액용 microchip을 탑재할 수 있는 $Genspector^{TM}$을 사용하여 수행하였다. DNA 증폭과 융점분석을 포함한 총 PCR 검색 시간은 HIV_1 및 HIV-2 모두에서 15분 이내로 완료되었으며, 각기 최소 2.3개의 합성 env 유전자로부터도 HIV-1 특이 117염기와 HIV-2 특이 119염기의 PCR산물을 성공적으로 증폭시킬 수 있는 민감성을 보여주었다. 이런 형식의 실시간 PCR법을 본 연구에서 초고속실시간 PCR (Ultra-rapid real-time PCR)이라 명명하였다. 이는 본 연구의 대상인 HIV에 대한 보조적 진단방법일 뿐 아니라 PCR 검색법이 사용되고 있는 다른 병원체에 대하여도 적용될 수 있을 것이나, 우선 HIV 임상시료에 대한 본 검색법의 효용성 실험 등 추가 연구가 필요할 것으로 사료된다.

• KSBB Journal
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• 제23권5호
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• pp.398-402
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• 2008

Cyanobacteria havebeen identified as one of the most promising group producing novel biochemically active natural products. Cyanobacteria are a very old group of prokaryotic organisms that produce very diverse secondary metabolites, especially non-ribosomal peptide and polyketide structures. Though many useful natural products have been identified in cyanobacterial biomass, cyanobacteria produce also extracellular proteins related with NRPS/PKS. Detection of unknown secondary metabolites in medium was carried in the present study by a screening of 98 cyanobacterial strains. A degenerated PCR technique as molecular approaches was used for general screening of NRPS/PKS gene in cyanobacteria. A putative PKS gene was detected by DKF/DKR primer in 38 strains (38.8%) and PCR amplicons resulted from a presence of NRPS gene were showed by MTF2/MTR2 primer in 30 strains (30.6%) and by A3/A7 primer in 26 strains (26.5%). HPLC analysis for a detection of natural products was performed in extracts from medium in which cyanobacteria containing putative PKS or NRPS were cultivated. CBT57, CBT62, CBT590 and CBT632 strains were screened for a production of extracellular natural products. 5 pure substances were detected from medium of these cyanobacteria.

• 생태와환경
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• 제40권1호
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• pp.149-154
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• 2007

남조류의 독성 잠재력을 확인하기 위해 microcystins 합성 유전자인 mcyB에 특이적으로 작용하는 TOX2P/TOX2M primer쌍을 이용한 whole-cell PCR을 실시하였다. 환경시료를 대상으로 한 실험 결과에서 TOX2P/TOX2M primer쌍은 약 1,000 $cells{\cdot}mL^{-1}$의 낮은 밀도에서 효과적으로 mcyB 유전자의 증폭에 성공하였으며, mcyB유전자를 지닌 종들은 모두 ELISA분석에 의해 microcystins의 생성이 확인되었다. 따라서, TOX2P/TOX2M primer쌍은 국내의 수체에서 독성 남조류의 신속하고 효과적인 검출을 위한 유용한 probe로 판단되었다.

• Journal of Microbiology and Biotechnology
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• 제12권3호
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• pp.417-422
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• 2002

Gene fusions were constructed by the transcriptional fusion of the dnaK promoter of pseudomonas sp. DJ-12 or E. coli to the lux or luc marker gene. The dnaKp-DJ::luxCDABE bioluminescent fusion in the biosensor using the Pseudomonas sp. DJ-12 dnaK promoter exhibited about 5-fold more extensive response to ethanol than that of dnaKp-EC::luxCDABE. The bioluminescent response of the dnaK-DJ::luc fusion to ethanol was much weaker than those of the other fusions. The biosensor harboring the dnaKp-DJ::luCDABE fusion was examined for its bioluminescence production based on exposure to aromatic compounds, such as biphenyl, 4-chlorobiphenyl (4CB), 4-hydroxybenzoate (4HBA), and catechol. In particular, the bioluminescence produced by the dnaKp-DJ::luxCDABE fusion was most sensitive to 1 mM biphenyl and 4CB when exposed for 80 min, and the responses were also very strong to other aromatics. Therefore, the biosensor bearing the dnaKp-DJ::luxCDABE fusion would appear to be the most useful for the detection of aromatics and other pollutants.

• ALGAE
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• 제35권2호
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• pp.133-144
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• 2020

Pythium porphyrae is responsible for devastating outbreaks in seaweed farms of Pyropia, the most valuable cultivated seaweed worldwide. While the genus Pythium contains many well studied pathogens, the genome of P. porphyrae has yet to be sequenced. Here we report the first available gene repertoire of P. porphyrae and a preliminary analysis of pathogenicity-related genes. Using ab initio detection strategies, similarity based and manual annotation, we found that the P. porphyrae gene repertoire is similar to classical phytopathogenic Pythium species. This includes the absence of expanded RxLR effector family and the detection of classical pathogenicity-related genes like crinklers, glycoside hydrolases, cellulose-binding elicitor lectin-like proteins and elicitins. We additionally compared this dataset to the proteomes of 8 selected Pythium species. While 34% of the predicted proteome appeared specific to P. porphyrae, we could not attribute specific enzymes to the degradation of red algal biomass. Conversely, we detected several cellulases and a cutinase conserved with plant-pathogenic Pythium species. Together with the recent report of P. porphyrae triggering disease symptoms on several plant species in lab-controlled conditions, our findings add weight to the hypothesis that P. porphyrae is a reformed plant pathogen.

• Journal of Microbiology and Biotechnology
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• 제14권4호
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• pp.737-744
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• 2004

A multiplex polymerase chain reaction (PCR) was developed for the simultaneous detection and differentiation among Vairimorpha spp. and Nosema spp. and identification of Vairimorpha necatrix from Lepidoptera insects. Three sets of primers were selected from different genomic sequences to specifically amplify an 831 bp amplicon within the SSU rRNA gene, specific for both Vairimorpha spp. and Nosema spp. (MSSR primer); a 542 bp amplicon within the SSU rRNA gene, specific for Vairimorpha spp. (VSSU primer); and a 476 bp amplicon within the actin gene, specific for Vairimorpha necatrix (VNAG primer). Using the primers in conjunction with multiplex PCR, it was possible to detect Vairimorpha spp. and Nosema spp. and to differentiate between them. The sensitivity of this PCR assay was approximately 10 spores per milliliter. It is proposed that the multiplex PCR is a sensitive, specific, and rapid tool that can serve as a useful differential diagnostic tool for detecting Vairimorpha spp. and Nosema spp. in Lepidoptera insect.

• Journal of Microbiology and Biotechnology
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• 제17권4호
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• pp.673-676
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• 2007

A two-step triplex PCR assay targeting the mecA, femA, and nuc genes was developed for the detection of methicillin resistance genes harbored by some Staphylococcus aureus isolates and for the simultaneous identification of such isolates at the species level. The triplex PCR revealed the presence of the femA and nuc genes in all the S. aureus isolates examined (n=105). Forty-four clinical isolates were mecA positive and no foodborne isolates were mecA positive. The PCR results had a 98 or 99% correlation with the results of PBP2a latex agglutination tests or oxacillin susceptibility tests, respectively.

• 한국동물위생학회지
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• 제32권2호
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• pp.103-109
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• 2009

Influeza type A virus have been worldwide problematic in animals as well as in humans. In this study, the use of reverse-transcriptase polymerase chain reaction (RT-PCR) was described for detecting influenza virus type A. The primer of RT-PCR was designed from an nonstructural (NS) gene of Influenza A virus. By RT-PCR, a product with the size of 189 bp was detected only when influenza virus type A was used as template. No products could be detected with Influenza virus type B as well as other respiratory pathogens. The detection limit of the RT-PCR was up to $10^{0.3}TCID_{50}$ which is comparable to the sensitivity of cell culture method. The RT-PCR could detect the influenza A virus from nasal turbinates of the ferrets infected with influenza virus type A not type B.

• Food Science and Biotechnology
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• 제14권3호
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• pp.387-391
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• 2005

Competitive polymerase chain reaction (cPCR) was used to develop a direct enumeration method of Listeria monocytogenes in pork meat. Pork meat was artificially inoculated with L. monocytogenes and DNA was extracted using guanidine thiocyanate-phenol-chloroform and subjected to PCR amplification. Sixteen primer sets for L. monocytogenes hlyA gene were tested for sensitive detection and the DG69/DG74 primer set was selected. The detection limit achieved with this primer set was as low as 860 colony-forming units (cfu) per 0.1 g of pork meat. When the samples were cultured at $30^{\circ}C$ for 16 hr in Brain Heart Infusion (BHI) medium, even a single bacterium could be detected with this primer set by PCR. For cPCR, the hlyA gene, which features a 148 bp-deletion, was cloned in the pGEM-4Z vector. A known amount of competitor DNA which has the same primer binding sites was co-amplified with L. monocytogenes total DNA from the artificially inoculated pork meat. The cell-number determined by cPCR was approximately equal to cfu from the Most Probable Number (MPN) method. The whole procedure took only 5 hr.

• 식물조직배양학회지
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• 제28권3호
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• pp.165-171
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• 2001

Adenosine deaminase 유전자를 연초의 형질전환용 표지유전자로 활용할 때 형질전환체 여부를 매우 빠르고 눈으로 직접 색깔을 확인할 수 있는 새로운 방법이 개발되었다. ADA 효소는 독성인 adenosine 유도체를 비독성인 inosine 유도체와 암모니아로 변환시키는데, 이때 형성된 암모니아를 phenol-nitoprusside와 alkaline-hypochlorite 용액을 이용하여 청색으로 변환시켜 96 well plate상에서 1시간 내에 형질전환체 여부를 쉽게 확인할 수 있게 되었다. ADA효소의 substrate로서 9-D-arabinofuranosyl adenine, cordycepin, 2'-deoxyadenosine, adenosine and xylofuranosyl adenine이 모두 가능하였으며, substrate 용액의 최적조건은 adenosine 10 mM과 pH 7.5이었다. 특히 형질전환체는 ADA효소의 inhibitor인 deoxycoformycin이 함유되어 있는 용액 속에서는 adenosine을 inosine과 암모니아로 변환시키지 못해 색깔의 변화가 없었는데, 이는 형질전환체에서 색깔의 변화는 ADA효소의 작용 때문에 일어나는 것을 의미한다. 따라서 본 연구결과는 ADA 표지유전자가 도입된 형질전환체의 확인에 있어서 GUS gene system과 같이 눈으로 직접 확인할 수 있을 뿐만 아니라 매우 작은 크기의 형질전환체 절편으로 쉽고, 빠르면, 값싸게 확인할 수 있게 되었다.