• 제목/요약/키워드: protein structures

검색결과 587건 처리시간 0.032초

Disruptions of Two Apparent rho-Independent Transcription Terminator Structures do not help in Enhancing the Expression of aceK in E. coli

  • Lee, Su-Ji;Chung, Taeo-Wan
    • BMB Reports
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    • 제28권5호
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    • pp.458-463
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    • 1995
  • Two apparent rho-independent transcription terminator structures within the coding sequence of aceK have been destroyed to access their roles in the differential expression between aceA and aceK in the glyoxylate bypass operon of E. coli. The effect of mutations on the expression of aceK was evaluated in two different ways: one by maxicell labeling and the other by lacZ fusion gene construction. The maxicell labeling experiment with the mutant operon clones has failed, like that of the wild type operon clone, to visibly show isocitrate dehrogenase (IDH) kinase/phosphatase, the product of aceK, on the autoradiogram of a protein gel. When the same mutations were introduced into an aceK::lacZ fusion gene to quantitatively evaluate the mutational effect, the activity of ${\beta}-galactosidase$ in neither of the mutant versions of the fusion gene was elevated significantly enough to explain the degree of polarity observed in this region. Thus, we conclude that neither of these intragenic, apparent rho-independent transcription terminator structures, which have long been suspected as a major determinant in the down regulation of aceK, really act as a premature transcriptional terminator.

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Effects of Chaperones on mRNA Stability and Gene Expression in Escherichia coli

  • Yoon, Hyun-Jin;Hong, Ji-Young;Ryu, Sang-Ryeol
    • Journal of Microbiology and Biotechnology
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    • 제18권2호
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    • pp.228-233
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    • 2008
  • Effects of chaperones on mRNA stability and gene expression were studied in order to develop an efficient Escherichia coli expression system that can maximize gene expression. The stability of mRNA was modulated by introducing various secondary structures at the 5'-end of mRNA. Four vector systems providing different 5'-end structures were constructed, and genes encoding GFPuv and endoxylanase were cloned into the four vector systems. Primer extension assay revealed different mRNA half-lives depending on the 5'-end secondary structures of mRNA. In addition to the stem-loop structure at the 5'-end of mRNA, coexpression of dnaK-dnaJ-grpE or groEL-groES, representative heat-shock genes in E. coli, increased the mRNA stability and the level of gene expression further, even though the degree of stabilization was varied. Our work suggests that some of the heat-shock proteins can function as mRNA stabilizers as well s protein chaperones.

된장의 향미에 미치는 ${\beta}-cyclodextrin$의 포접효과 (Effects of ${\beta}-cyclodextrin$ inclusion on the flavor of Doenjang)

  • 김혜영B;김순미
    • 한국식생활문화학회지
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    • 제16권4호
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    • pp.316-322
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    • 2001
  • This study was performed to investigate flavor modification effects of ${\beta}-cyclodextrin$ $({\beta}-CD)$ inclusion complex on the flavor of Doenjang (Korean traditional fermented soy paste) with various substitution levels of 10, 20, and 30%. Water and protein contents of the substituted samples showed significantly lower values compared to those of control(p<0.05). Results of DSC(Differential Scanning Calorimetry) showed that significantly higher ${\Delta}H$ values (386.03 and 304.23) in the 20 and 30% substituted samples represented the stabilized internal cell structures(p<0.05). Internal structures observed with the scanning electronic microscope tended to be less rough and organized making even and ordered internal cell structures as the substitution levels were increased. Results of sensory evaluation showed significantly higher savory flavor and significantly lower bitter and astringent flavors with the substituted samples compared to those of control(p<0.05). Results from this study showed the substitutions of ${\beta}-CD$ could possibly modify unfavored flavors of Doenjang while keeping the unique, nutritional and functional properties when ${\beta}-CD$ was used as a flavor modifier.

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단백질 부분 구조를 위한 효율적인 오류 허용 알고리즘 (An Efficient Fault Tolerant Apriori Algorithm for Local Protein Structures)

  • 김계형;김민호;허준호
    • 한국정보과학회:학술대회논문집
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    • 한국정보과학회 2003년도 봄 학술발표논문집 Vol.30 No.1 (A)
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    • pp.869-871
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    • 2003
  • 단백질 부분 구조는 일종의 단백질 패턴으로써 진화적인 성질을 띄고 있다. 본 논문에서는 단백질 간의 열 안정성과 이러한 단백질 부분 구조 간의 관련성에 대해서 알아보고자 한다. 또한 오류 허용 알고리즘 (FT-Apriori)의 성능을 향상시킬 수 있는 효과적인 기법을 제안한다. 이러한 기법을 단백질 부분 구조에 적용시킴으로써 실제 단백질 데이터에서 그 효용성을 일아본다.

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In silico High-Throughput Screening by Hierarchical Chemical DB Search by 3D Pharmacophore Model

  • Shin, Jae-Min
    • 대한약학회:학술대회논문집
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    • 대한약학회 2002년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2
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    • pp.181-182
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    • 2002
  • Recentadvancesin '-omics ' technologies enable us to discover more diverse disease- relevant target proteins, which encourages us to find out more target-specific novel lead compounds as new drug candidates. Therefore, high-throughput screening (HTS) becomes an essential tool in this area. Among many HTS tools, in silico HTS is a very fast and cost-effective tool to try to derive a new lead compound for any new targets, especially when the target protein structures are known or readily modeled. (omitted)

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Lead Informatics Using Protein 3D-Structures

  • Ro, Seong-Gu;Shin, Dong-Kyu;Han, Hui-Jong;Jeon, Young-Ho;Jeong, Eui-Jun;Hwang, Kwang-Yeon;Kim, Hye-Yeon;Heo, Yong-Seok;Lee, Tae-Gyu;Kim, Jin-Hwan
    • 대한약학회:학술대회논문집
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    • 대한약학회 2001년도 Proceedings of the Pharmaceutical Society of Korea
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    • pp.77-77
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    • 2001
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Skin biopsy: an emerging method for small nerve fiber evaluation

  • Sohn, Eun Hee
    • Annals of Clinical Neurophysiology
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    • 제20권1호
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    • pp.3-11
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    • 2018
  • Skin biopsy and staining the specimens with immuno-reactive markers has been proven to be a useful method to demonstrate the pathologic status of small nerve fibers. Quantification of intraepidermal nerve fiber density using anti-protein gene product 9.5 antibody is a standard method to diagnose small fiber neuropathy. Skin biopsy also makes it possible to differentiate the nerve fibers according to their function by using different markers. Quantification of dermal structures with different types of nerve fibers could reveal the pathophysiologic mechanism of the disease state.

단백질 구조 비교를 위한 이차구조의 상관관계 계산 (Calculation of Relation between Secondary Structures for Protein Structure Comparison)

  • 조민수;안건태;이명준;이수현
    • 한국정보과학회:학술대회논문집
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    • 한국정보과학회 2003년도 봄 학술발표논문집 Vol.30 No.1 (A)
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    • pp.890-892
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    • 2003
  • 단백질 구조의 표현 방법을 정형화하고 호환성 및 상호작용성을 향상하기 위하여 단백질의 이차구조 구성요소와 그들 사이의 관계를 이용하여 단백질 구조를 기술하는 PSA가 제안되었다. 본 논문에서는 PSA에서 정의된 단백질의 이차구조 사이에 정의된 요소 중에서 네 가지의 각도관계와 다섯 가지의 거리관계를 계산하는 방법에 대하여 기술하였으며, 이를 자바로 구현하여 그 결과를 확인하였다. 본 논문에서 제안한 방법은 단백질의 이차구조 사이의 상관관계를 포함하는 PSAML 데이터로부터 단백질의 구조 및 유사성을 비교하기 위한 단백질 구조비교 시스템에서 사용할 수 있다.

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