• Journal of Microbiology and Biotechnology
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• 제28권6호
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• pp.931-937
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• 2018

Glycosyltransferases (GTs) from microbes are an emerging and rich source for efficient glycol-transformation of natural/unnatural compounds. Here, we probed the catalytic capability and substrate promiscuity of BmmGT1 from marine-derived Bacillus methylotrophicus B-9987. The regioselectivity of BmmGT1 on macrolactin A (1) was explored by optimization of the reaction conditions, in which a series of O-glycosylated macrolactins (1a-1e) were generated, including two new di/tri-O-glucosyl analogs (1b and 1e). Furthermore, BmmGT1 was able to catalyze the glycosylation of the thiol (S-) or amine (N-) sites of phenolic compounds (2 and 3), leading to the generation of N- (2a) or S-glycosides (3a and 3b). The present study demonstrates that BmmGT1 could serve as a potential enzyme tool for O-, N-, or S-glycosyl structural diversification of compounds for drug discovery.

• 대한간호학회지
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• 제50권4호
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• pp.501-512
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• 2020

Purpose: The purpose of this study was to analyze articles published in the Journal of the Korean Academy of Nursing (JKAN) between 2010 and 2019, along with those published in three international nursing journals, to improve JKAN's international reputation. Methods: The overall characteristics of JKAN's published papers and keywords, study participants, types of nursing interventions and dependent variables, citations, and cited journals were analyzed. Additionally, the keywords and study designs, publication-related characteristics, journal impact factors (JIF), and Eigenfactor scores of International Journal of Nursing Studies (IJNS), International Nursing Review (INR), Nursing & Health Sciences (NHS), and JKAN were analyzed and compared. Results: Among the four journals, JKAN's score was the lowest in both the journal impact factor and Eigenfactor score. In particular, while the JIF of INR and NHS has been continuously increasing; JKAN's JIF has remained static for almost 10 years. The journals which had cited JKAN and those which JKAN had cited were mainly published in Korean. Conclusion: JKAN still has a low IF and a low ranking among Social Citation Index (E) journals during the past 10 years, as compared to that of four international journals. To enhance JKAN's status as an international journal, it is necessary to consider publishing it in English and to continuously improve the conditions of other publications.

• 천문학회지
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• 제53권6호
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• pp.161-168
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• 2020

We report the discovery of a giant exoplanet in the microlensing event OGLE-2017-BLG-1049, with a planet-host star mass ratio of q = 9.53 ± 0.39 × 10-3 and a caustic crossing feature in Korea Microlensing Telescope Network (KMTNet) observations. The caustic crossing feature yields an angular Einstein radius of θE = 0.52 ± 0.11 mas. However, the microlens parallax is not measured because the time scale of the event, tE ≃ 29 days, is too short. Thus, we perform a Bayesian analysis to estimate physical quantities of the lens system. We find that the lens system has a star with mass Mh = 0.55+0.36-0.29 M⊙ hosting a giant planet with Mp = 5.53+3.62-2.87 MJup, at a distance of DL = 5.67+1.11-1.52 kpc. The projected star-planet separation is a⊥ = 3.92+1.10-1.32 au. This means that the planet is located beyond the snow line of the host. The relative lens-source proper motion is μrel ~ 7 mas yr-1, thus the lens and source will be separated from each other within 10 years. After this, it will be possible to measure the flux of the host star with 30 meter class telescopes and to determine its mass.

• 한국동물위생학회지
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• 제44권4호
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• pp.185-194
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• 2021

Polyglutamine extension in the coding sequence of mutant huntingtin causes neuronal degeneration associated with the formation of insoluble polyglutamine aggregates in Huntington's disease (HD). Mutant huntingtin can form aggregates within the nucleus and processes of neurons possibly due to misfolding of the proteins. To better understand the mechanism by which an elongated polyglutamine causes aggregates, we have developed an in vitro binding assay system of polyglutamine tract from truncated huntingtin. We made GST-HD exon1 fusion proteins which have expanded polyglutamine epitopes (e.g., 17, 23, 32, 46, 60, 78, 81, and 94 CAG repeats). In the present emergence of new study adjusted nanotechnology on protein chip such as surface plasmon resonance strategy which used to determine the substance which protein binds in drug discovery platform is worth to understand better neurodegenerative diseases (i.e., Alzheimer disease, Parkinson disease and Huntington disease) and its pathogenesis along with development of therapeutic measures. Hence, we used strengths of surface plasmon resonance (SPR) technology which is enabled to examine binding specificity and explore targeted molecular epitope using its electron charged wave pattern in HD pathogenesis utilize conjugated mutant epitope of HD protein and its interaction whether wild type GST-HD interacts with mutant GST-HD with maximum binding affinity at pH 6.85. We found that the maximum binding affinity of GST-HD17 with GST-HD81 was higher than the binding affinities of GST-HD17 with other mutant GST-HD constructs. Furthermore, our finding illustrated that the mutant form of GST-HD60 showed a stronger binding to GST-HD23 or GST-HD17 than GST-HD60 or GST-HD81. These results indicate that the binding affinity of mutant huntingtin does not correlate with the length of polyglutamine. It suggests that the aggregation of an expanded polyglutamine might have easily occurred in the presence of wild type form of huntingtin.

• Journal of Microbiology and Biotechnology
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• 제32권8호
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• pp.1041-1046
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• 2022

Nucleoside deoxyribosyltransferase (NDT) is an enzyme that replaces the purine or pyrimidine base of 2'-deoxyribonucleoside. This enzyme is generally used in the nucleotide salvage pathway in vivo and synthesizes many nucleoside analogs in vitro for various biotechnological purposes. Since NDT is known to exhibit relatively low reactivity toward nucleoside analogs such as 2'-fluoro-2'-deoxynucleoside, it is necessary to develop an enhanced NDT mutant enzyme suitable for nucleoside analogs. In this study, molecular evolution strategy via error-prone PCR was performed with ndt gene derived from Lactobacillus leichmannii as a template to obtain an engineered NDT with higher substrate specificity to 2FDU (2'-fluoro-2'-deoxyuridine). A mutant library of 214 ndt genes with different sequences was obtained and performed for the conversion of 2FDU to 2FDA (2'-fluoro-2'-deoxyadenosine). The E. coli containing a mutant NDT, named NDT^L59Q, showed 1.7-fold (at 40℃) and 4.4-fold (at 50℃) higher 2FDU-to-2FDA conversions compared to the NDT^WT, respectively. Subsequently, both NDT^WT and NDT^L59Q enzymes were over-expressed and purified using a His-tag system in E. coli. Characterization and enzyme kinetics revealed that the NDT^L59Q mutant enzyme containing a single point mutation of leucine to glutamine at the 59^th position exhibited superior thermal stability with enhanced substrate specificity to 2FDU.

• 천문학논총
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• 제38권3호
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• pp.125-145
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• 2023

This study investigates the integration of astronomy-related topics in the Korean national science curricula spanning from 1945 to 2023. We analyze the placement and extent of astronomy content across different school levels. Astronomy contents in the science curricula have changed in response to social needs (e.g., practical knowledge required for agriculture and fishery) and advancement in astronomical research (e.g., the discovery of exoplanets and the suggestion of new cosmological parameters). Contents addressing the motions of celestial objects and stellar physical properties have remained relatively consistent. In the latest 2022 revised national curriculum, scheduled for implementation in 2024, several elements, such as coordinate systems, have been removed, while the inquiry activities using digital tools are emphasized. The incorporation of the cosmic perspectives in the national curriculum, as well as astronomy education within the context of education for sustainable development, remains limited even in the most recent curriculum. For future life revisions, the active participation of researchers is needed to reflect the latest astronomical research progress and scientific characteristics in the field of astronomy.

• Journal of Microbiology and Biotechnology
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• 제34권2호
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• pp.467-475
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• 2024

ρ-Hydroxyacetophenone is an important and versatile compound that has been widely used in medicine, cosmetics, new materials, and other fields. At present, there are two ways to obtain ρ-hydroxyacetophenone. One is to extract it from plants, such as Artemisia capillaris Thunb and Cynanchum otophyllum Schneid, and the other is to synthesize it by using chemical methods. Of these two methods, the second is the main one, although it has problems, such as flammable and explosive reagents, difficult separation of by-products, and harsh reaction conditions. To solve these issues, we adopted genetic engineering in this study to construct engineered Escherichia coli containing Hped gene or EbA309 gene. Whole-cell biotransformation was conducted under the same conditions to select the engineered E. coli with the higher activity. Orthogonal tests were conducted to determine the optimal biotransformation condition of the engineered E. coli. The results showed that the optimal condition was as follows: substrate concentration of 40 mmol/l, IPTG concentration of 0.1 mmol/l, an induction temperature of 25℃, and a transformation temperature of 35℃. Under this condition, the effects of transformation time on the ρ-hydroxyacetophenone concentration and cell growth were further studied. We found that as the transformation time extended, the ρ-hydroxyacetophenone concentration showed a gradually increasing trend. However, when the ρ-hydroxyacetophenone concentration increased to 1583.19 ± 44.34 mg/l in 24 h, cell growth was inhibited and then entered a plateau. In this research, we realized the synthesis of ρ-hydroxyacetophenone by biotransformation, and our findings lay a preliminary foundation for further improving and developing this method.

• Molecules and Cells
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• 제40권7호
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• pp.466-475
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• 2017

Dietary supplements have exhibited myriads of positive health effects on human health conditions and with the advent of new technological advances, including in the fields of proteomics, genomics, and metabolomics, biological and pharmacological activities of dietary supplements are being evaluated for their ameliorative effects in human ailments. Recent interests in understanding and discovering the molecular targets of phytochemical-gene-protein-metabolite dynamics resulted in discovery of a few protein signature candidates that could potentially be used to assess the effects of dietary supplements on human health. Persimmon (Diospyros kaki) is a folk medicine, commonly used as dietary supplement in China, Japan, and South Korea, owing to its different beneficial health effects including anti-diabetic implications. However, neither mechanism of action nor molecular biomarkers have been discovered that could either validate or be used to evaluate effects of persimmon on human health. In present study, Mass Spectrometry (MS)-based proteomic studies were accomplished to discover proteomic molecular signatures that could be used to understand therapeutic potentials of persimmon leaf extract (PLE) in diabetes amelioration. Saliva, serum, and urine samples were analyzed and we propose that salivary proteins can be used for evaluating treatment effectiveness and in improving patient compliance. The present discovery proteomics study demonstrates that salivary proteomic profile changes were found as a result of PLE treatment in prediabetic subjects that could specifically be used as potential protein signature candidates.

• 대한화장품학회지
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• 제43권2호
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• pp.137-147
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• 2017

피부의 생태계는 미생물에게 다양한 형태의 서식처를 제공하며, 광범위한 미생물들이 살고 있다. 숙주인 사람은 이들과 공생관계를 이루고 있으며, 이들은 숙주에 많은 긍정적인 영향을 미친다. 피부에 분포하는 미생물들의 다양한 대사물질은 피부세포에 영향을 미치고, 피부장벽 기능, 노화방지 및 항염증에 광범위한 효능을 나타내는 것으로 알려져 있다. 본 연구에서는 사람의 피부에서 신규한 Sporichthyaceae bacterium strain K-07을 분리하였고, 해당 미생물의 16S rRNA 분석결과 Sporichthya속의 미생물과 상동성이 93.4%인 것으로 신규속(genus)으로 확인되었다. 그리고 신규로 분리된 K-07 배양액을 처리하였을 때, HaCaT cell에 어떤 변화가 나타나는지에 대한 분석을 실시하였다. 분리된 신규 미생물 strain K-07의 16S rRNA sequence 분석결과 상동성이 93.4% 이하로 확인되었고, 보고되지 않은 새로운 종으로 확인되었다. Filaggrin, cluadin1, claudin4, ${\alpha}SMase$, 및 CerS3 / HAS3 및 aquaporin3 / IL-6 및 TNF-${\alpha}$ / TSLP 및 TARC를 대상으로 strain K-07 배양액을 처리하여 변화를 관찰하였다. 그 결과 filaggrin, cluadin1, claudin4, ${\alpha}$SMase, 및 CerS3 / HAS3 및 aquaporin3에서는 음성 대조군 대비 우수한 증가 효과가 나타남을 확인하였다. 그리고 IL-6 및 TNF-${\alpha}$ / TSLP 및 TARC에 대해서도 우수한 억제능을 나타내는 것을 확인하였다. 결론적으로 신규 미생물 strain K-07 배양액은 피부 장벽활성 증진에 매우 효과적인 작용을 하며, 염증 억제에 우수한 효능을 나타내는 것으로 확인되므로 피부에 효과적인 소재로 사용될 수 있을 것이다.

• 비교문화연구
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• 제33권
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• pp.143-169
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• 2013

Recently, because of the danger and damages that following the steady development of scientific technologies, natural science is faced with many humane and ethical problems. So it is asserted the interdisciplinary with social and human science. However, it comes commonly that the ethical issues such as world view and one's view of life caused the development of sociology, especially development of the market economy. But in many cases, the interdisciplinary can be useful for widen the view of scholars. The interdisciplinary is actually connected with the problems of philosophy, and located in that domain. In this case, this is noticed as a model to the philosophers in 18th century, especially Denis Diderot. Diderot published De $l^{\prime}interpr{\acute{e}}tation$ de la nature during editing the Encyclopedia, from there he picked out the contents from piles of documents of Encyclopedia. Even though the contents or opinions of De $l^{\prime}interpr{\acute{e}}tation$ de la nature are inaccuracy or erroneous, it shows that how human-social science and natural science encountered. Diderot studied mathematics and then Diderot accepted to the natural science proposal, he approaches philosophy with translate English books to the French. Next he understood natural science by reading Buffon and Maupertuis, and during working for Encyclopedia, he possessed his knowledge that he can claim his opinion to other scholars. However in this De $l^{\prime}interpr{\acute{e}}tation$ de la nature, Diderot who sometimes rebutted other scholars' theory and demonstration, tried to build a philosophy on metaphysics in order to it was important for himself that he imposed the methods of science and importance of experience. Anyhow, this De $l^{\prime}interpr{\acute{e}}tation$ de la nature cause consider the recognition of Diderot in the field of natural science, and is suggested as a model about his Nature. This mean that it is an expression of his philosophy, and the content is found from natural philosophy and empirical philosophy. Like giving these attache the importance of method study for science and technique, these are targeted the promotion of popularization of natural-science and scientific-technology. Also it advocates fulfilling from reasonable philosophy to empirical philosophy. Therefore, the philosophy which was speculative and abstracted became his philosophy which was writing the meaning, as waiting the discovery of science. And at that time, the humanities made interdisciplinary with natural science.