• Journal of Microbiology and Biotechnology
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• 제17권8호
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• pp.1390-1393
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• 2007

In this study, three of the representative EDCs, $17{\beta}$-estradiol, bisphenol A, and styrene, were employed to find their mode of toxic actions in E. coli. To accomplish this, four different stress response genes, recA, katG, fabA, and grpE genes, were used as a representative for DNA, oxidative, membrane, or protein damage, respectively. The expression levels of these four genes were quantified using a real-time RT-PCR after challenge with three different EDCs individually. Bisphenol A and styrene caused high-level expression of recA and katG genes, respectively, whereas $17{\beta}$-estradiol made no significant changes in expression of any of those genes. These results lead to the classification of the mode of toxic actions of EDCs on E. coli.

• 생태와환경
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• 제41권3호
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• pp.331-337
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• 2008

Polycyclic aromatic hydrocarbons (PAHs) derived from leakage of fossil fuels and incomplete combustion of organic materials have been considered as harmful contaminants in environments. This study evaluated the effect of benzo[k]fluoranthene (BkF), one of the PAHs, using the multiple biomarkers and applied the integration model with those biomarker responses. After 10 days of the exposure at the measured concentrations of BkF (6, 25, and 45 ${\mu}g\;L^{-1}$), the changes of the four biomarkers, that is, 7-ethoxyresorufin-O-deethylase (EROD), DNA single-strand breaks (Comet), acetylcholinesterase (AChE) and vitellogenin (VTG) in the common carp (Cyprinus carpio) were observed. The standardized values of four biomarker responses were computed and integrated as star plots, representing Integrated Biomarker Respnse (IBR) values. DNA damage was induced in a dose-dependent manner, and increased significantly compared with that in the control. EROD and VTG levels were significantly elevated at low concentrations of BkF. On the other hand, AChE activities were not altered by BkF. IBR values increased as the exposure concentrations increased. Thus, the metabolic, endocrine and genetic changes of the biomarker responses in the common carp exposed to BkF should be considered in the case of the ecological risk assessment of the BkF in fish and it can be used as a biomonitoring tool in aquatic ecosystems. In addition, star plots can be used as a useful analysis tool in multibiomarker integration approach.

• 한국균학회지
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• 제49권4호
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• pp.545-553
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• 2021

In 2021, seven yeast strains were isolated from earthworm (Eisenia andrei) gut samples collected from the Nanji Water Regeneration Center in Goyang City, Gyeonggi Province, Korea. A total of seven yeasts were isolated, of which three strains have not been previously reported in Korea. To identify the yeasts, pairwise sequence comparisons of large subunit (LSU) rDNA sequences were performed using the basic local alignment search tool (BLAST). Assimilation test and cell morphology analysis were performed using the API 20C AUX kit and phase contrast microscope, respectively. Five of the seven strains were assigned to the genus Candida of the order Saccharomycetales of the class Saccharomycetes, and two to the genus Apiotrichum of the order Trichosporonales of the class Tremellomycetes. The yeast strain Candida sojae E2 belongs to the family Debaryomycetaceae, and Apiotrichum laibachii E8 and A. laibachii E9 belong to the family Trichosporonaceae. All strains were cultured in yeast mold agar for three days and showed different colony forms. C. sojae E2 was round and entire shaped, while A. laibachii E8 and A. laibachii E9 was round and convex shaped. This study focuses on the description of the three yeast strains that have not been officially reported in Korea.

• 한국식품과학회지
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• 제37권6호
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• pp.1005-1011
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• 2005

본 연구에서는 높은 분리능을 가지고 있을 뿐만 아니라 실험의 재현성과 경제성의 측면에서도 많은 장점을 갖고 있는 ERIC DNA sequence를 응용한 ERIC-PCR을 이용하여 Salmonella, E. coli, Shigella, Vibrio 등 4속의 주요 그람 음성 식중독유발 세균들의 분리 동정 방법을 확립하고자 하였다. ERIC-PCR 결과, E. coli의 경우 0.3kb, 0.42kb 및 1.2kb의 band가 모든 균주에서 공통적으로 확인되었고, Salmonella속으로부터는 0.22kb, 0.4kb 및 0.7kb의 band가 증폭되었다. Shigella속은 모든 표준균주와 분리균주로부터 0.33kb와 1.25kb의 band가 증폭되었으며, S. sonnei의 경우 위의 주요 2개 band 이외에도 대부분의 균주에서 0.44kb, 2.0kb 및 3.05kb의 band가 증폭되어 다른 종의 Shigella와 구별되는 fingerprinting pattern을 나타내었다. 그리고 V. parahaemolyticus의 경우 표준균주와 분리균주 모두 0.51kb와 1.5kb의 band가 증폭되어 V. cholerae, V. mimicus 등과 같은 다른 종의 Vibrio와 구별되는 fingerprinting pattern을 나타내었다. 이와 같이 4속의 모든 식중독 균주마다 ERIC-PCR후 생성되는 fingerprinting pattern에서 3-5개의 공통적인 band가 증폭되는 것이 확인되어 이를 이용한 속 수준의 분리 동정과 이러한 주요 band들 이외의 부수적인 band들을 고려하여 종 수준까지의 분리도 가능함을 확인하였다. 따라서 본 연구의 결과는 ERIC 반복적 DNA 염기서열을 이용한 ERIC-PCR이 식중독균의 분리 동정 방법으로 사용될 수 있음을 확인하였으며, 나아가 더 많은 속(genus)의 식중독세균을 대상으로 한 새로운 분리 동정 방법을 확립하는데도 응용이 될 수 있을 것이다.

• Fisheries and Aquatic Sciences
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• 제15권2호
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• pp.151-155
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• 2012

We used nine microsatellite DNA markers to estimate genetic variation among wild and cultured populations of the sea squirt Halocynthia roretzi. The loci were polymorphic, with 6-32 alleles, and allelic richness ranged from 6.0 to 26.1 in each population. The wild and the cultured populations had similar mean heterozygosities ($H_O$ and $H_E$), allele numbers, and allelic richness. One cultured population with softness syndrome had a lower mean in the observed heterozygosity ($H_O$ = 0.57) and higher mean inbreeding coefficient ($F_{IS}$ = 0.261) than any other populations. This suggests that the loss of genetic variation in the diseased population might be due to increased inbreeding. A neighbor-joining tree and pairwise population estimates of $F_{ST}$ showed moderate genetic differentiation between the wild and the cultured populations. Additionally, the softness syndrome population was genetically divergent from wild populations, but it was genetically close to the cultured populations.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2005년도 생물공학의 동향(XVII)
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• pp.243-246
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• 2005

A novel esterase showing high enantioselectivity to (S)-ketoprofen ethyl ester was selected from fosmid environmental DNA library which is provided by Microbial Genomic & Applications Center. As a result of Blast search, the gene wasn't registerated in Gene Bank yet. And as we know, conserved domain region of esterase , G-X-S-X-G, wasn't discovered.$^{4)}$ And it is similar to Beta-lactamase. The DNA sequence of cloned esterase include an open reading frame consisting of 1170 bp, designated as EST-Y29, encoding a protein of 389 amino acids with a molecular mass of about 42.8 kDa. And amino acid sequence analysis revealed only a few identity (28%) to tile known esterases/lipases in the databases containing the conserved sequence motifs of esterases/lipases. when being comparison to other esterase revealed , this enzyme seems to be classified as a new member of esterase family. EST-Y29 was functionally overexpressed in a soluble form in E. coli with maximum conversion yield of (S)-ketoprofen at $65^{\circ}C$. This study demonstrates that functional screening combined with the sequential uses of restriction enzymes to exclude already known enzymes is a useful approach for isolating novel enzyme from a metagenome.

• Toxicological Research
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• 제20권2호
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• pp.109-116
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• 2004

For the safety evaluation of adenovirus-mediated gene transfer, we investigated differential gene expressions after transfecting adenoviral vector containing p16 tumor suppressor gene (Ad5CMV-p16) into human non-small cell lung cancer cells. In the previous study, we showed adenovirus-mediated $p16^{INK4a}$ gene transfer resulted in significant inhibition of cancer cell growth. We investigated gene expression changes after transfecting Ad5CMV-p16, Ad5CMV (null type, a mock vector) into A549 cells by using cDNA chip and oligonucleotide microarray chip (1200 genes) which carries genes related with signal transduction pathways, cell cycle regulations, oncogenes and tumor suppressor genes. We found that $p16^{INK4a}$ gene transfer down regulated 5 genes (cdc2, cyclin D3, cyclin B, cyclin E, cdk2) among 26 genes involved in cell cycle regulations. Compared with serum-free medium treated cells, Ad5CMV-p16 changed 27 gene expressions, two fold or more on oligonucleotide chip. In addition, Ad5CMV-p16 did not seem to increase the tumorigenicity-related gene expression in A549 cells. Further studies will be needed to investigate the effect of Ad5CMV-p16 on normal human cells and tissues for safety evaluation.

• 식물분류학회지
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• 제43권1호
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• pp.12-21
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• 2013

본 연구에서는 제주황기(Astragalus nakaianus)의 분류학적 위치를 명확히 하고 한국산 재배황기(A. mongholicus cultivar)의 올바른 학명을 부여하기 위하여 외부형태형질과 ITS 그리고 5구간의 cp non-coding DNA의 염기서열을 조사하였다. 또한 9개의 마이크로새털라이트 마커를 이용하여 3집단 61개체에 대한 유전적 구조가 분석되었다. 그 결과, 남한산 재배황기와 A. mongholicus var. dahuricus 사이에서는 형태와 ITS 염기서열상에서 유의한 차이점이 없었다. 제주황기는 A. mongholicus var. mongholicus 그리고 var. dahuricus와 줄기의 습성, 식물체의 길이, 엽축의 길이, 소엽의 길이 등에서 형태적으로 차이를 보였다. ITS와 cp non-coding 구간 염기서열에서 제주황기는 황기(A. mongholicus)와 차이점을 보이지 않았지만, 마이크로새털라이트 분석에서 제주황기와 남한산 재배황기간에 뚜렷하게 구분된 구조를 보였다. 이러한 결과들을 보았을 때, 한국산 재배황기는 A. mongholicus var. dahuricus로 처리해야 하며 제주황기는 A. mongholicus의 변종으로서 취급되어야 한다.

• 센서학회지
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• 제27권4호
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• pp.237-241
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• 2018

The real-time enrichment and detection of pathogens are serious issues and rapidly evolving field of research because of the ability of these pathogens to cause infectious diseases. In general, bacterial detection is accomplished by conventional colony counting or by polymerase chain reaction (PCR) after DNA extraction. As colony counting requires considerable time to cultivate, PCR is an attractive method for rapid detection. A small number of pathogens can cause diseases. Hence, a pretreatment process, such as enrichment is essential for detecting bacteria in an actual environment. Thus, in this study, we developed a microfluidic chip capable of performing rapid enrichment of bacteria and the extraction of their genes. A lectin, i.e., Concanavalin A (ConA), which shows binding affinity to the surface of most bacteria, was coated on the surface of magnetic particles to nonspecifically capture bacteria. It was subsequently concentrated through magnetic forces in a microfluidic channel. To lyse the captured bacteria, magnetic particles were irradiated by a wavelength of 532nm. The photo-thermal effect on the particles was sufficient for extracting DNA, which was consequently utilized for the identification of bacteria. Our device will help monitor the existence of bacteria in various environmental situations such as water, air, and soil.

• Animal cells and systems
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• 제2권3호
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• pp.383-388
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• 1998

A RecA-like protein (RecAps) was identified from fluorescent Pseudomonas sp. and the inducible nature of the protein was characterized in detail. It was shown by dose-response and time-course experiments using two DNA damaging agents, nalidixic acid and mitomycin-C, that the cellular level of RecAps protein was increased 3-8 fold compared to that of the control. The most effective doses of nalidixic acid and mitomycin-C for the protein induction were $30{\mu}g/ml$ and $0.3{\mu}g/ml$ at the treatment time point of 150 min, respectively. The enhanced level of RecAps protein was gradually decreased to the control level after 10 hr in normal medium. Interestingly, the cellular level of RecAps protein was increased by the same DNA damaging agents even when cell growth was completely inhibited by treatment with $170{\mu}g/ml$ of chloramphenicol, an inhibitor of protein synthesis, suggesting that new protein synthesis is not required for the induction of RecAps. All these results suggest that a typical S0S repair function driven by RecA-like protein is conserved in Pseudomonas sp. cells as in E, coli.