• BMB Reports
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• 제31권6호
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• pp.525-535
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• 1998

A critical step in the faithful translation of genetic information is specific tRNA recognition by aminoacyl-tRNA synthetases. These enzymes catalyze the covalent attachment of particular amino acids to the terminal adenosine of cognate tRNA substrates. In general, there is one synthetase for each of the twenty amino acids and each enzyme must discriminate against all of the cellular tRNAs that are specific for the nineteen noncognate amino acids. Primary sequence information combined with structural data have resulted in the division of the twenty synthetases into two classes. In recent years, several high-resolution co-crystal structures along with biochemical data have led to an increased understanding of tRNA recognition by synthetases of both classes. The anticodon sequence and the amino acid acceptor stem are the most common locations for critical recognition elements. This review will focus on acceptor stem discrimination by class II synthetases. In particular, the results of in vitro aminoacylation assays and site-directed and atomic group mutagenesis studies will be discussed. These studies have revealed that even subtle atomic determinants can provide signals for specific tRNA aminoacylation.

• 대한화학회지
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• 제11권4호
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• pp.126-131
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• 1967

各 種 아민(triethylamine, diethylamine, pyridine, diphenylamine, dimethylaniline)과 各種 Electron Acceptor($CCl_4,\;ICl,\;I_2$)를 Hexane 溶媒 存在下에서 作用시킨 結果 各各 Charge Transfer Complex를 形成하였으나 그 形成能은 아민의 Basicity에 比例하였고 Electron Donor의 Polarity의 差가 클 때에는 다른 形式의 Complex를 形成함을 紫外線 吸收 分光法으로 確認하였다. Complex 形成能과 아민의 Basicity 및 Electron Acceptor의 Polarity의 關係를 論하였다.

• 한국식품영양과학회지
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• 제29권5호
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• pp.802-806
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• 2000

Cellobiose에 당전이 효소인 dextransucrase를 여러 가지 조건별로 반응시켜 올리고당의 생성경향을 알아보았다. Cellobiose에 대한 acceptor 반응의 최적조건은 cellobiose와 surcose의 비율은 3:1, 효소의 양은 2 U/mL, buffer의 이온강도는 25 mM, pH는 5, 반응온도는 $25^{\circ}C$로 나타났다. Cellobiose의 acceptor products는 종합도 6까지 생성되었으며, 구조는 2-O-isomaltodextrinyl cellobiose로 추정하였다.

• 한국재료학회:학술대회논문집
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• 한국재료학회 2001년도 춘계학술발표강연 및 논문개요집
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• pp.74-74
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• 2001

• Archives of Pharmacal Research
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• 제26권12호
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• pp.1047-1054
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• 2003

Molecular chaperones have a crucial role in the folding of nascent polypeptides in endoplasmic reticulum. Some of them are known to be sensitive to the modification by electrophilic metabolites of organic pro-toxicants. In order to identify chaperone proteins sensitive to alkyators, ER extract was subjected to alkylation by 4-acetamido-4 -maleimidyl-stilbene-2,2 -disulfonate (AMS), and subsequent SDS-PAGE analyses. Protein spots, with molecular mass of 160, 100, 57 and 36 kDa, were found to be sensitive to AMS alkylation, and one abundant chaperon protein was identified to be protein disulfide isomerase (PDI) in comparison with the purified PDI. To see the reactivity of PDI with cysteine alkylators, the reduced form ($PDI_{red}$) of PDI was incubated with various alkylators containing Michael acceptor structure for 30 min at $38^{\circ}C$ at pH 6.3, and the remaining activity was determined by the insulin reduction assay. Iodoacetamide or N-ethylmaleimide at 0.1 mM remarkably inactivated $PDI_{red}$ with N-ethylmaleimide being more potent than iodoacetamide. A partial inactivation of $PDI_{oxid}$ was expressed by iodoacetamide, but not N-ethylmaleimide (NEM) at pH 6.3. Of Michael acceptor compounds tested, 1,4-benzoquinone ($IC_{50}, 15 \mu$ M) was the most potent, followed by 4-hydroxy-2-nonenal and 1,4-naphthoquinone. In contrast, 1,2-naphthoquinone, devoid of a remarkable inactivation action, was effective to cause the oxidative conversion of $PDI_{red}$ to $PDI_{oxid}$. Thus, the action of Michael acceptor compounds differed greatly depending on their structure. Based on these, it is proposed that POI, one of chaperone proteins in ER, could be susceptible to endogenous or xenobiotic Michael acceptor compounds in vivo system.

• 한국인구학
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• 제7권1호
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• pp.39-77
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• 1984

It has been well known that the family pjanning programme has a great deal with declining fertility in Korea. The present study was aimed to measure the impact of family planning program me on fertility level. The specific objectives are to overview the demographic changes ncluding fertility declining and to calculate actual number of birth averted during the last 20 years. The data used for the present study was collected from various sources such as service statistics of the government, survey and research reports, and other related papers. The tool used for calculation of birth prevention was "Standard Couple Years of Protection (SCYP) Method" developed by M Gorosh. The major findings are summarized as follows ; Total of family planning acceptors from 1962 to 1982 was 9,556,153. On the basis of this data, total of averted births was calculated for eachcontraceptive Method ; 1.Oral pills, total number of acceptors from 1968 to 1982 was 2.347,259. Estimated number of birth averted was 272 ,303 .70 and the Coefficient of births prevention per acceptor turned out to be 0.114 2.Condoms, total number of birth acceptors from 1962 to 1982 was 2,874,216. Estimated number of birth averted was 220,495.30 and the coefficient of births prevention per acceptor turned out to be 0.077. 3.IUD, total number of acceptors from 1962 to 1982 was 5,101 .650. Estimated number of birth averted was 1,377,584.76 and the coefficient of births prevention per acceptor turned out to be 0.270. 4.Vasectomy, total number of acceptors from 1962 to 1982 was 556,508. Estimated number of birth averted was 626 ,128 .80 and the coefficient of births prevention per acceptor turned out to be 1.125. 5.Tubaligation total number of birth acceptors from 1972 to 1982 was 1 210,775. Estimated number of birth averted was 1 ,117 679.00 and thecoefficient of birtlts prevention per acceptor turned nut to be 0.923. 6.Abortion, total number of acceptors from 1973 to 1982 was 465,525. Estimated number of birth averted was 355 ,283 .60 and the coefficient of births prevention per acceptor turned out to be 0.763.

• 폴리머
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• 제31권2호
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• pp.136-140
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• 2007

Carbazole(electron donor)그룹과 dinitrobenzene(electron acceptor)그룹을 이용하여 전하 이동 작용이 실세스퀴옥산/고분자 하이브리드의 형성 메커니즘으로서 작용할 수 있는지 살펴보는 연구를 진행하였다. 하이브리드 실험은 새롭게 합성된 Poly(carbazole-styrene) (PS/D)와 dinitrobenzyl silsesquioxane (Cube/A)의 톨루엔 용액을 혼합/캐스팅을 하여 만들어진 필름을 이용하였으며 상분리가 없는 투명한 하이브리드 필름이 일부 조건에서 얻어졌다. PS/D및 Cube/A의 $^1H-NMR$분석, 그리고 하이브리드 필름들의 UV 흡수 실험은 실세스퀴옥산에 의한 입체 장애 효과가 없는 조건에서는 acceptor와 donor가 1:1로 전하 이동 착물을 형성할 수 있지만, 상분리가 없는 투명한 실세스퀴옥산 하이브리드는 acceptor/donor의 비율이 0.7 : 1 이하에서 형성된다는 것을 보여주었다. 이 결과들은 또 실세스퀴옥산 한 분자 당 평균 4개의 전하 이동 착물이 형성된다는 하이브리드 나노 구조에 대한 정보도 제공하였다.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2007년도 춘계학술대회
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• pp.241-241
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• 2007

• Bulletin of the Korean Chemical Society
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• 제32권8호
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• pp.2787-2790
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• 2011

• 한국진공학회:학술대회논문집
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• 한국진공학회 2016년도 제50회 동계 정기학술대회 초록집
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• pp.432.2-432.2
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• 2016

A new A-D-A type (Acceptor-Donor-Acceptor) conjugated based on pyridine-borane complex (Donor), non-boron fluorine (Donor) and 2,5-bis(alkyl)-3,6-di(thiophen-2-yl)pyrrolo[3,4-c]pyrrole-1,4(2H,5H)-dione (DPP) (Acceptor) were designed and synthesized via Pd-catalyzed Suzuki cross-coupling reaction. The synthesized boron based complex exhibited high electron affinity, which indicates deep HOMO energy levels and good visible absorption led to their use as donors in BHJ (bulk heterojunction) solar cells. Inverted devices were fabricated, reaching open-circuit voltage as high as 0.91eV. To probe structure-property relationship and search for design principle, we have synthesized pyridine-boron based electron donating small molecules. In this study, we report a new synthetic approach, molecular structure, charge carrier mobility and morphology of blended film and their correlation with the photovoltaic J-V characteristics in details.