• 한국재료학회:학술대회논문집
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• 한국재료학회 1993년도 춘계학술발표회
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• pp.116-116
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• 1993

• Bulletin of the Korean Chemical Society
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• 제30권5호
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• pp.1139-1142
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• 2009

Refinement of NMR structures by molecular dynamics (MD) simulations with a solvent model has improved the structural quality. In this study, we applied MD refinement with the generalized Born (GB) implicit solvent model to protein structure determined under membrane-like environments. Despite popularity of the GB model, its applications to the refinement of NMR structures of hydrophobic proteins, in which detergents or organic solvents enclose proteins, are limited, and there is little information on the use of another GB parameter for these cases. We carried out MD refinement of crambin NMR structure in dodecylphosphocholine (DPC) micelles (Ahn et al., J. Am. Chem. Soc. 2006, 128, 4398-4404) with GB/Surface area model and two different surface tension coefficients, one for aquatic and the other for hydrophobic conditions. Our data show that, of two structures by MD refinement with GB model, the one refined with the parameter to consider hydrophobic condition had the better qualities in terms of precision and solvent accessibility.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2005년도 춘계학술대회
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• pp.615-617
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• 2005

[ $^{13}C$ ] NMR spectra were obtained for pure $CH_4$ hydrate in order to identify hydrate structure and cage occupancy of guest molecule. The NMR technique can provide both qualitative and quantitative hydrate characteristics. The moles of methane captured into pure $CH_4$ hydrate per mole of water were found to be similar to the full occupancy value. The overall results drawn from this study can be usefully applied to storage and transportation of natural gas.

• 한국자기공명학회논문지
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• 제20권2호
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• pp.46-49
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• 2016

MiRNA-155, upregulated in various cancers, is one of the miRNAs that suppress apoptosis of human cancer. Thus, inhibition of the maturation of miRNA-155 could be an effective way to induce apoptotic cancer cell death. The apical stem-loop of the pre-miRNA-155 has been known as a Dicer biding site for RNA cleavage. Here, to understand the molecular basis of the tertiary interaction between pre-miRNA-155 with Dicer, we characterize the structure of the apical stem-loop of pre-miRNA-155 using NMR spectroscopy. The RNA has a stem-bulge-stem-loop-stem structure, which is consist of G-C Watson-Crick and G-U Wobble base pairs. The assignments of imino- protons were further confirmed by 2D $^{15}N-^1H$ HSQC NMR spectrum. The NMR parameters obtained in this study can be further used to investigate the tertiary interaction between pre-miRNA-155 and other biomolecules such as protein, nucleic acids, or small chemicals which might be used to control the apoptosis of cancer.

• 한국자기공명학회논문지
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• 제23권1호
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• pp.33-39
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• 2019

Studies on the interactions of proteins with partner molecules at the atomic resolution are essential for understanding the biological function of proteins in cells and for developing drug molecules. Solution NMR spectroscopy has shown remarkably useful capability for investigating properties on the weak to strong intermolecular interactions in both diluted and crowded solution such as cell lysates. Of note, the state-of-the-art in-cell NMR method has made it possible to obtain atomistic information on natures of intermolecular interactions between target proteins with partner molecules in living cells. In this mini-review, we comprehensively describe the several technological advances and developments in the in-cell NMR spectroscopy.

• 공업화학
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• 제4권4호
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• pp.770-775
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• 1993

에틸렌글리콜과 1, 4-시클로헥산디메탄올의 테레프탈산 공중합체인, poly(ethylene terephthalate-co-1, 4-cyelohexylene dimethylene terephthalate), P(ET-CT)의 화학 구조를 고분해능 NMR 분석을 통하여 조사하였다. $^1H$ NMR 분석에서 메칠렌기에 의한 chemical shift가 ET, 트란스 CT, 및 시스 CT로 분리됨에 따라 공중합조성 및 이성질체의 비율을 구할 수 있었다. $^{13}C$ NMR 분석에서 카르보닐기에 연결된 벤젠기의 탄소가 diad로 분리됨에 따라 공중합 연쇄 분포(copolymer sequence distribution)를 구한 결과, P(ET-CT) 공중합체는 랜덤공중합체임이 판명되었다. 아울러 랜덤 통계식을 이용하여 공중합 연쇄의 분포 및 평균길이를 구할 수 있었다.

• 한국자기공명학회논문지
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• 제17권1호
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• pp.59-66
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• 2013

BldD, a developmental transcription factor from Streptomyces coelicolor, is a homodimeric, DNA-binding protein with 167 amino acids in each subunit. Each monomer consists of two structurally distinct domains, the N-terminal domain (BldD-NTD) responsible for DNA-binding and dimerization and the C-terminal domain (BldD-CTD). In contrast to the BldD-NTD, of which crystal structure has been solved, the BldD-CTD has been characterized neither in structure nor in function. Thus, in terms of structural genomics, structural study of the BldD-CTD has been conducted in solution, and in the present work, mainchain NMR assignments of the recombinant BldD-CTD (residues 80-167 of BldD) could be achieved by a series of heteronuclear multidimensional NMR experiments on a [$^{13}C/^{15}N$]-enriched protein sample. Finally, the secondary structure prediction by CSI and TALOS+ analysis using the assigned chemical shifts data identified a ${\beta}-{\alpha}-{\alpha}-{\beta}-{\alpha}-{\alpha}-{\alpha}$ topology of the domain. The results will provide the most fundamental data for more detailed approach to the atomic structure of the BldD-CTD, which would be essential for entire understanding of the molecular function of BldD.

• Bulletin of the Korean Chemical Society
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• 제29권5호
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• pp.911-912
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• 2008

• 한국실천공학교육학회논문지
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• 제4권2호
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• pp.84-90
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• 2012

화학분석 설계의 한 사례로서 디지털 기록매체 중 하나인 CD-R (Compact Disc Recordable) 기록층의 단면구조와 기록층의 주요성분인 염료의 구성성분 및 화학구조를 분석하기 위해 분석계획을 수립하고 분석을 수행하는 전 과정을 기술하였다. 미지시료의 화학분석은 많은 경험과 지식을 요하는 복잡한 과정이기 때문에 학생들이 화학분석을 위한 설계 절차를 수립하고 분석방법의 선택이나 자료해석 등에 어려움을 겪고 있어 이해를 돕기 위한 사례로서 CD-R 개발단계에서 실제로 수행했던 한 제품분석의 전 과정을 제시하였다. 본 연구에서는 SEM을 사용하여 CD-R의 substrate (기판) 및 기록층 (Dye 층)의 단면적 구조를 확인하였다, 기록층인 염료는 적절한 용매를 이용하여 용해 수집한 후 TLC (얇은 막 크로마토그래피)를 이용해 성분별로 분리하였다. 분리된 각 성분을 UV-Vis 흡수분광법으로 흡광도를 측정하여 정량하였고, GC-MS와 NMR을 이용해 각 성분의 화학구조를 분석하고 질량분석법을 통해 최종적으로 질량을 확인하였다.

• 한국자기공명학회논문지
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• 제18권1호
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• pp.5-9
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• 2014

In last three decades, RNA molecules have been revealed to play the central roles in many cellular processes. Structural understanding of RNA molecules is essential to interpret their functions, and many biophysical techniques have been adopted for this purpose. NMR spectroscopy is a powerful tool to study structures and dynamics of RNA molecules, and it has been further applied to study tertiary interactions between RNA molecules, RNA-protein, and RNA-small molecules. This short article accounts for the general methods for NMR sample preparations, and also partially covers the resonance assignments of structured RNA molecules.