• 한국인터넷방송통신학회논문지
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• 제18권1호
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• pp.223-229
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• 2018

본 논문에서는 이미지에서 검출된 각 연결성분들의 위상적 지속구간 정보를 그래프 기반 이미지 세그멘테이션에 결합하여 보다 안정적인 이미지 세그멘테이션 기법을 제안한다. 이미지의 밝기 또는 색상정보 등을 이용하여 모스 함수를 정의하고 이의 레벨세트로부터 각 연결성분의 위상적 지속구간을 구한다. 각 연결성분이 생성되고 긴 지속구간을 갖는 연결성분에 적절히 병합되는 과정을 영 차원 호몰로지 군의 관점에서 설명한다. 다양한 특성을 갖는 이미지들에 대하여 짧은 지속구간을 갖는 연결성분들을 지속구간이 긴 인근 성분에 적절히 병합시키는 과정을 통하여 보다 안정적인 이미지 세그멘테이션 결과들 얻을 수 있음을 실험으로 확인한다.

• BMB Reports
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• 제45권12호
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• pp.736-741
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• 2012

Certain members of the cytochromes P450 superfamily metabolize polyunsaturated long-chain fatty acids to several classes of oxygenated metabolites. An approach based on in silico analysis predicted that Streptomyces peucetius CYP107N3 might be a fatty acid-metabolizing enzyme, showing high homology with epoxidase enzymes. Homology modeling and docking studies of CYP107N3 showed that oleic acid can fit directly into the active site pocket of the double bond of oleic acid within optimum distance of $4.6{\AA}$ from the Fe. In order to confirm the epoxidation activity proposed by in silico analysis, a gene coding CYP107N3 was expressed in Escherichia coli. The purified CYP107N3 was shown to catalyze $C_9-C_{10}$ epoxidation of oleic acid in vitro to 9,10-epoxy stearic acid confirmed by ESI-MS, HPLC-MS and GC-MS spectral analysis.

• Parasites, Hosts and Diseases
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• 제35권2호
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• pp.105-110
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• 1997

T. sergenti 국내 분리주의 면역항원인 33 kDa의 piroplasm surface protein 유전자를 크로닝하였다. 크로닝된 T. sergenti의 33 kDa에 해당하는 유전자의 염기서열을 분석한 결과 총 869 bps의 염기와 283개의 아미노산을 확인하였다. 또 이들 분석결과를 일본주의 염기서열 및 아미노산 조성과 비교 분석하였던 바 각각 99.4. 98.9%의 homology를 나타내었으므로 두 주간의 p33 유전자는 거의 일치하는 것으로 판명되었다.

• 미생물학회지
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• 제38권4호
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• pp.267-275
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• 2002

미생물 유전체 프로젝트의 결과인 유전체 서열에 대해, 비교 유전체 분석을 수행할 수 있는 분석 도구인 GComp를 개발하였다. 이 도구는 국부 상동성 계산을 BLAST나 FASTA를 사용하여 수행한 후에 그 결과를 받아들여, 상동성을 보이는 부분을 분석하고 위치 파악 및 연결한 뒤, 두 유전체간의 상동성 정도를 일목요연하게 보여줄 수 있는 테이블과 파일들을 생성한다. 한편. 그 결과를 그래픽으로 표시하고 전체를 살펴볼 수 있는 인터페이스 기능을 구현하였다. 시험 데이터로 기존의 미생물 유전체 서열을 상대로 분석하면서, 유전체 서열의 핵산 및 단백질 수준에서의 비교분석 결과를 통해 두 유전체에 대한 비교 정보를 효과적으로 확인할 수 있었고, 보다 다양한 분석을 위한 도구 개발의 기준을 설정할 수 있었다.

• 한국식물병리학회지
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• 제11권1호
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• pp.73-79
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• 1995

Complementary DNAs (cDNAs) to the coat protein gene of an ordinary Korean strain of potato virus Y (PVY-OK) isolated from potato (cv. Superior) were synthesized and cloned into a plasmid pUC119 and sequenced. The RNA of the virus propagated in tobacco (Nicotinaa sylvestris) was extracted by the method of phenol extraction. The first strand of cDNAs to the coat protein penomic RNA of the virus was made by Moloney murine leukemia virus reverse transcriptase. The cDNA were synthesized and amplified by the method of polymerase chain reaction (PCR) using a pair of oligonucleotide primers. PVYCP3P and PVYCP3M. The size of cDNAs inserted in pUC119 plasmid was estimated as about 840 bp upon agarose gel electrophoresis. Double stranded cDNAs were transformed into the competent cell of E. coli JM109. Sequence analysis of cDNAs was conducted by the dideoxynucleotide chain termination method. Homology of cDNAs of the PVY-OK coat protein genomic RNA with those of PVY-O (Japan), PVY-T (Japan), PVY-TH (Japan), PVYN (The Netherlands),and PVYY (France) was represented as 97.3%, 88.9%, 89.3%, 89.6% and 98.5%, respectively. Homology at the amino acid level turned out to the be 97.4%, 92.5%, 92.9%, 92.9% and 98.5%, respectively.

• Applied Biological Chemistry
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• 제32권1호
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• pp.64-72
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• 1989

Near full length cDNA clones encoding the rice seed storage protein, prolamine, were isolated and divided into two homology classes based on cross-hybridization and DNA sequencing analysis. These cDNA clones contain a single open reading frame encoding a putative rice prolamine precursor(M.W.=17,200) possessing atypical 14 amino acid signal peptide. Clones of these two homology classes diverge mainly by insertions/deletions of short nucleotide stretches and point mutations. The deduced primary structures of both types of prolamine polypeptides are devoid of any major tandem repetitive sequences, a feature prevalent in other cereal prolamines. No significant homology teas detected between the rice prolamine and other cereal prolamines, indicating that the rice gene evolved from a different ancestor that gave rise to other cereal prolamine genes. Developing wheat and rice endosperms were examined using ultrathin sections prepared from tissues harvested at various days after flowering. By immunocytochemical localization techniques, wheat prolamines are localized within vesicles from Golgi apparatus and in homogeneous regions of protein bodies. The involvement of the goli apparatus in the packaging of wheat prolamines into protein bodies indicates a pathway which differs from the mode of other cereal prolamines and resembles the mechanism employed for the storage of rice glutelin and legume globulins.

• Bulletin of the Korean Chemical Society
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• 제24권9호
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• pp.1256-1260
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• 2003

Two O-methyltransferases, OMTII-1 and OMTII-4 of meadow rue Thalictrum tuberosum showed a high sequence identity. Of 364 amino acids only one residue is not the same, which is Tyr21 or Cys21. Even if the 21st residues in these OMTs are not included in the binding sites of the enzymes, binding affinities of the enzyme homodimers over the same substrate are very different. While the binding affinity of one homodimer over caffeic acid is 100%, that of the other is 25%. Authors tried to predict the three-dimensional structures of Thalictrum tuberosum O-methyltransferases using homology-based modelling by a comparison with caffeic acid O-methyltransferase, and explain the reason of the phenomenon mentioned above based on their three dimensional structural studies. In the enzyme homodimer, the better binding affinity may be caused by the shorter distance between the 21st residue and the binding site of the other monomer.

• Bulletin of the Korean Chemical Society
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• 제28권6호
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• pp.941-946
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• 2007

Bacillus halodurans O-methyltransferase (BhOMT) is a S-adenosylmethionine (SAM or AdoMet) dependent methyltransferase. Three dimensional structure of the BhOMT bound to S-adenosyl-L-homocysteine (SAH or AdoHcy) has been determined by comparative homology modeling. BhOMT has 40% sequence identity with caffeoyl-CoA 3-O-methyltransferase (CCoAOMT) from alfalfa. Based on x-ray structure of CCoAOMT, three dimensional structure of BhOMT was determined using MODELLER. The substrate binding sites of these two proteins showed slight differences, but these differences were important to characterize the substrate of BhOMT. Automated docking study showed that four flavonoids, quercetin, fisetin, myricetin, and luteolin which have two hydroxyl groups simultaneously at 3'- and 4'-position in the B-ring and structural rigidity of Cring resulting from the double bond characters between C2 and C3, were well docked as ligands of BhOMT. These flavonoids form stable hydrogen bondings with K211, R170, and hydroxyl group at 3'-position in the Bring has stable electrostatic interaction with Ca2+ ion in BhOMT. This study will be helpful to understand the biochemical function of BhOMT as an O-methyltransferase for flavonoids.

• Journal of Microbiology and Biotechnology
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• 제22권7호
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• pp.917-922
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• 2012

Homology modeling of Streptomyces peucetius CYP147F1 was constructed using three cytochrome P450 structures, CYP107L1, CYPVdh, and CYPeryF, as templates. The lowest energy SPCYP147F1 model was then assessed for stereochemical quality and side-chain environment by Accelrys Discovery Studio 3.1 software. Further activesite optimization of the SPCYP147F1 was performed by molecular dynamics to generate the final SPCYP147F1 model. The substrate limonene was then docked into the model. The model-limonene complex was used to validate the active-site architecture, and functionally important residues within the substrate recognition site were identified by subsequent characterization of the secondary structure. The docking of limonene suggested that SPCYP147F1 would have broad specificity with the ligand based on the two different orientations of limonene within the active site facing to the heme. Limonene with C7 facing the heme with distance of $3.4{\AA}$ from the Fe was predominant.

• 대한수학회보
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• 제59권4호
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• pp.917-928
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• 2022

Let R be a commutative Noetherian ring and I an ideal of R. In this paper, we study colocalization of generalized local homology modules. We intend to establish a dual case of local-global principle for the finiteness of generalized local cohomology modules. Let M be a finitely generated R-module and N a representable R-module. We introduce the notions of the representation dimension r^I(M, N) and artinianness dimension a^I(M, N) of M, N with respect to I by r^I(M, N) = inf{i ∈ ℕ₀ : H^I_i(M, N) is not representable} and a^I(M, N) = inf{i ∈ ℕ₀ : H^I_i(M, N) is not artinian} and we show that a^I(M, N) = r^I(M, N) = inf{r^IR_𝔭 (M_𝔭,𝔭N) : 𝔭 ∈ Spec(R)} ≥ inf{a^IR_𝔭 (M_𝔭,𝔭N) : 𝔭 ∈ Spec(R)}. Also, in the case where R is semi-local and N a semi discrete linearly compact R-module such that N/∩_t>0I^tN is artinian we prove that inf{i : H^I_i(M, N) is not minimax}=inf{r^IR_𝔭 (M_𝔭,𝔭N) : 𝔭 ∈ Spec(R)＼Max(R)}.