• Title/Summary/Keyword: Binding study

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Binding of IciA protein to the dnaA promoter region

  • Kim, Hakjung;Hwang, Deog-Su
    • Journal of Microbiology
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    • v.33 no.3
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    • pp.191-195
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    • 1995
  • IciA protein has been shown as an inhibitor for the initiation of E. coli chromosomal DNA replication at oriC. IciA protein binds the AT-rich region in oriC and then blocks the initiation of chromosomal DNA replication. Two binding sites for IciA protein were identified in dnaA gene, encoding the initiator for the E. coli chromosomal replication, promoter region by gel-shift assay and DNase I footprinting, One, named as IciA site I, is located upstream of the dnaA promoter 1P. The other, named as IciA site II, is located downstream of the dnaA promoter 2P. The sequence comparison of the regions protected from the DNase I cleavage did not result in a clear consensus sequence for the binding of IciA protein, suggesting that IciA protein may be a member of multimeric complex dsDNA binding proteins. This study provided information about the binding mode of IciA protein. Even though the IciA site II and IciA binding site in oriC seem to be composed of two IciA binding units, one binding unit is likely enough to cause the binding of IciA protein to the IciA site I. The binding of IciA protein to the dna4 promoter implies that IciA protein may involve not only the control of the initiation of chromosomal DNA replication but also the control of the dna4 gene expression.

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NMR Study of the pH Effect on the DNA Binding Affinity of Human RPA

  • Lee, Min-Woo;Choi, Ju-Hyeok;Choi, Jae-Gyu;Lee, Ae-Ree;Lee, Joon-Hwa
    • Journal of the Korean Magnetic Resonance Society
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    • v.20 no.3
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    • pp.71-75
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    • 2016
  • The replication protein A (RPA) plays a crucial role in DNA replication, recombination, and repair. RPA consists of 70, 32 and 14 kDa subunits and has high single-stranded DNA (ssDNA) binding affinity. The largest subunit, RPA70, mainly contributes to bind to ssDNA as well as interact with many cellular and viral proteins. In this study, we performed nuclear magnetic resonance experiments on the complex of the DNA binding domain A of human RPA70 (RPA70A) with ssDNA, d(CCCCC), at various pH, to understand the effect of pH on the ssDNA binding of RPA70A. The chemical shift perturbations of binding residues were most significant at pH 6.5 and they reduced with pH increment. This study provides valuable insights into the molecular mechanism of the ssDNA binding of human RPA.

Chloride binding isotherms of various cements basing on binding capacity of hydrates

  • Tran, Van Mien;Nawa, Toyoharu;Stitmannaithum, Boonchai
    • Computers and Concrete
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    • v.13 no.6
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    • pp.695-707
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    • 2014
  • This study investigated the chloride binding isotherms of various cement types, especially the contributions of C-S-H and AFm hydrates to the chloride binding isotherms were determined. Ordinary Portland cement (OPC), Modified cement (MC), Rapid-hardening Portland cement (RHC) and Low-heat Portland cement (LHC) were used. The total chloride contents and free chloride contents were analyzed by ASTM. The contents of C-S-H, AFm hydrates and Friedel's salt were determined by X-ray diffraction Rietveld (XRD Rietveld) analysis. The results showed that OPC had the highest chloride binding capacity, and, LHC had the lowest binding capacity of chloride ions. MC and RHC had very similar capacities to bind chloride ions. Experimental equations which distinguish the chemically bound chloride and physically bound chloride were formulated to determine amounts of the bound chloride basing on chloride binding capacity of hydrates.

Roles of Transcription Factor Binding Sites in the D-raf Promoter Region

  • Kwon, Eun-Jeong;Kim, Hyeong-In;Kim, In-Ju
    • Animal cells and systems
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    • v.2 no.1
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    • pp.117-122
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    • 1998
  • D-raf, a Drosophila homolog of the human c-raf-1, is known as a signal transducer in cell proliferation and differentiation. A previous study found that the D-raf gene expression is regulated by the DNA replication-related element (DRE)/DRE-binding factor (DREF) system. In this study, we found the sequences homologous to transcription factor C/EBP, MyoD, STAT and Myc recognition sites in the D-raf promoter. We have generated various base substitutional mutations in these recognition sites and subsequently examined their effects on D-raf promoter activity through transient CAT assays in Kc cells with reporter plasmids p5'-878DrafCAT carrying the mutations in these binding sites. Through gel mobility shift assay using nuclear extracts of Kc cells, we detected factors binding to these recognition sites. Our results show that transcription factor C/EBP, STAT and Myc binding sites in D-raf promoter region play a positive role in transcriptional regulation of the D-raf gene and the Myo D binding site plays a negative role.

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Ibuprofenlysine binding to human and bovine serum albumin using a fluorescence probe technique

  • Kim, Chong-Kook;Cha, Hyun-Sook;Kim, Yang-Bae;Yu, Byung-Sul
    • Archives of Pharmacal Research
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    • v.4 no.1
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    • pp.19-24
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    • 1981
  • The possibility of using a fluorescence probe technique for the study of ibuprofenlysine binding to human and bovine serum albumin was investigated. 1-anilino-8-naphalenesulfonate was used as the probe. The number of binding sites of human and bovine serum albumins for ibuprofenlysine appears to be 4 and 2, respectively. By using this technique, the association constants were found to be $1.533{\times}10^{4}M^{-1}$ and $2.238{\times}10^{4}M^{-1}$, respectively.

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The Hydrogen Binding Property Study by Density Functional Theory for Zr, V, Fe and Al (밀도 함수를 이용한 지르코니움, 바나듐, 철과 수소와의 반응성 연구)

  • Park, Taesung;Lee, Taeckhong
    • Journal of Hydrogen and New Energy
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    • v.25 no.6
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    • pp.602-608
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    • 2014
  • The sequence of bond overlap population of metal hydrogen binding is in Al-H > Fe-H > Zr-H > V-H. This results shows the binding energy of Al-H is the biggest in this metals (Al, Fe, Zr, and V) and hydrogen interaction. The Vanadium-hydrogen binding shows the weakest binding energy compared to other metals and it causes easy hydrogen desorption from the corresponding metals. The net charge of Al-H show the biggest value of 0.2248 and the severe localizations of electrons around aluminum and imply strongest covalent binding nature in these metals. This study is applicable to the purification of hydrogen in other bulk gas.

NMR Study of Temperature-Dependent Single-Stranded DNA Binding Affinity of Human Replication Protein A

  • Kim, Min-Gyu;Shin, Tae-Hoan;Choi, Seo-Ree;Choi, Jae-Gyu;Lee, Joon-Hwa
    • Journal of the Korean Magnetic Resonance Society
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    • v.20 no.3
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    • pp.66-70
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    • 2016
  • The replication protein A (RPA), is a heterotrimer with 70, 32 and 14 kDa subunits and plays a crucial role in DNA replication, recombination, and repair. The largest subunit, RPA70, binds to single-stranded DNA (ssDNA) and mediates interactions with many cellular and viral proteins. In this study, we performed nuclear magnetic resonance experiments on the complex of the DNA binding domain A of human RPA70 (RPA70A) with ssDNA, d(CCCCC), at various temperatures, to understand the temperature dependency of ssDNA binding affinity of RPA70A. Essential residues for ssDNA binding were conserved while less essential parts were changed with the temperature. Our results provide valuable insights into the molecular mechanism of the ssDNA binding of human RPA.

Sialic acid-binding protein from mushroom Paecilomyces japonica

  • Ryu, Chang-Soo;Kim, Ki-Don;Kim, Byung-Su;Kong, Kwang-Hoon;Kim, Ha-Hyung
    • Proceedings of the PSK Conference
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    • 2003.04a
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    • pp.317.1-317.1
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    • 2003
  • Carbohydrate-binding proteins have been isolated from various sources, including plants, animals, fungi, and bacteria, and they have been used extensively in the detection, localization, and isolation of glycoconjugates. Many carbohydrate-binding proteins are purified from mushrooms, however, only a few proteins with sialic acid-binding specificity have been reported. In the present study, a novel sialic acid-binding protein, designated PJA, has been purified from the mushroom Paecilomyces japonica. followed by extraction and affinity chromatography. (omitted)

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Hormonal Regulation of Insulin-Like Growth Factor Binding Protein Secretion by a Bovine Mammary Epithelial Cell Line

  • Kim, W.Y.;Chow, J.C.;Hanigan, M.D.;Calvert, C.C.;Ha, J.K.;Baldwin, R.L.
    • Asian-Australasian Journal of Animal Sciences
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    • v.10 no.2
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    • pp.233-239
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    • 1997
  • A mammary epithelial cell line (MAC-T) established as a model for lactation was utilized to identify and characterize effects of various hormones upon insulin-like growth factor binding protein secretion. Ligand and immunoblot analyses of conditioned media indicated that insulin-like growth factor binding protein-2 was secreted by MAC-T cells. Insulin-like growth factor-I stimulated insulin-like growth factor binding protein-2 secretion in a dose-dependent manner, but prolactin and bovine somatotropin did not alter insulin-like growth factor binding protein-2 secretion. Insulin increased and cortisol decreased insulin-like growth factor binding protein-2 secretion. Effects of insulin-like growth factor-I on insulin-like growth factor binding protein-2 secretion support previous studies using primary cultures of bovine mammary cells and bovine fibroblasts. Effects of cortisol and insulin on insulin-like growth factor binding protein-2 secretion may be explained by changes in protein synthesis. In addition, supraphysiological doses of insulin can cross-react with the insulin-like growth factor-I receptor and stimulate insulin-like growth factor binding protein-2 secretion. MAC-T cells provide a model system to study mechanisms that regulate local insulin-like growth factor-I bioactivity.

Assessment of Lipopolysaccharide-binding Activity of Bifidobacterium and Its Relationship with Cell Surface Hydrophobicity, Autoaggregation, and Inhibition of Interleukin-8 Production

  • Park, Myeong-Soo;Kim, Min-Jeong;Ji, Geun-Eog
    • Journal of Microbiology and Biotechnology
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    • v.17 no.7
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    • pp.1120-1126
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    • 2007
  • This study was performed to screen probiotic bifidobacteria for their ability to bind and neutralize lipopolysaccharides (LPS) from Escherichia coli and to verify the relationship between LPS-binding ability, cell surface hydrophobicity (CSH), and inhibition of LPS-induced interleukin-8 (IL-8) secretion by HT-29 cells of the various bifidobacterial strains. Ninety bifidobacteria isolates from human feces were assessed for their ability to bind fluorescein isothiocyanate (FITC)-labeled LPS from E. coli. Isolates showing 30-60% binding were designated LPS-high binding (LPS-H) and those with less than 15% binding were designated LPS-low binding (LPS-L). The CSH, autoaggregation (AA), and inhibition of LPS-induced IL-8 release from HT-29 cells of the LPS-H and LPS-L groups were evaluated. Five bifidobacteria strains showed high levels of LPS binding, CSH, AA, and inhibition of IL-8 release. However, statistically significant correlations between LPS binding, CSH, AA, and reduction of IL-8 release were not found. Although we could isolate bifidobacteria with high LPS-binding ability, CSH, AA, and inhibition of IL-8 release, each characteristic should be considered as strain dependent. Bifidobacteria with high LPS binding and inhibition of IL-8 release may be good agents for preventing inflammation by neutralizing Gram-negative endotoxins and improving intestinal health.