The Experts below are selected from a list of 607176 Experts worldwide ranked by ideXlab platform
Yukui Zhang - One of the best experts on this subject based on the ideXlab platform.
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epitope imprinted polymer coating cdte quantum dots for specific recognition and direct fluorescent quantification of the Target Protein bovine serum albumin
Biosensors and Bioelectronics, 2014Co-Authors: Yaqiong Yang, Yukui Zhang, Yizhi WangAbstract:A novel epitope molecularly imprinted polymer (EMIP) for specific recognition and direct fluorescent quantification of the Target Protein bovine serum albumin (BSA) was demonstrated where polymerization was performed on the surface of silica nanospheres embedded CdTe quantum dots (QDs). The synthetic peptide derived from the surface-exposed C-terminus of bovine serum albumin (BSA, residues 599-607) was selected as the template molecule. The resulting EMIP film was able to selectively capture the template peptide and the corresponding Target Protein BSA via the recognition cavities. Based on the fluorescence quenching, the EMIP-coated QDs (molecular imprinted polymer coating CdTe QDs using epitope as the template) nanospheres were successfully applied to the direct fluorescence quantification of BSA. Compared with BMIP-coated QDs (molecular imprinted polymer coating CdTe QDs using BSA as the template), the imprinting factor and adsorption capacity of EMIP-coated QDs were greatly increased. The prepared EMIP-coated QDs can also discriminate even one mismatched sequences from the original sequences of the epitope of the BSA. The practical analytical performance of the EMIP-coated QDs was examined by evaluating the detection of BSA in the bovine calf serum sample with satisfactory results. In addition, the resulting EMIP-coated QDs nanospheres were also successfully applied to separating BSA from the bovine blood sample.
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molecularly imprinted polymer anchored on the surface of denatured bovine serum albumin modified cdte quantum dots as fluorescent artificial receptor for recognition of Target Protein
Biosensors and Bioelectronics, 2012Co-Authors: Wei Zhang, Xiwen He, Yang Chen, Wenyou Li, Yukui ZhangAbstract:A new type of molecularly imprinted polymer (MIP)-based fluorescent artificial receptor was developed by anchoring MIP on the surface of denatured bovine serum albumin (dBSA) modified CdTe quantum dots (QDs) using the surface molecular imprinting process. The approach combined the merits of molecular imprinting technology and the fluorescent property of the CdTe QDs. The dBSA was used not only to modify the surface defects of the CdTe QDs, but also as assistant monomer to create effective recognition sites. Three different Proteins, namely lysozyme (Lyz), cytochrome c (Cyt) and methylated bovine serum albumin (mBSA), were tested as the template molecules and then the receptors were synthesized by sol–gel reaction (imprinting process). The results of fluorescence and binding experiments demonstrated the recognition performance of the receptors toward the corresponding template. Under optimum conditions, the linear range for Lyz was from 1.4 × 10−8 to 8.5 × 10−6 M, and the detection limit was 6.8 nM. Moreover, the new artificial receptors were applied to separate and detect Lyz in real samples. This fluorescent artificial receptor may serve as a starting point in the design of highly effective synthetic fluorescent receptor for recognition of Target Protein.
Finbarr Hayes - One of the best experts on this subject based on the ideXlab platform.
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pentapeptide scanning mutagenesis random insertion of a variable five amino acid cassette in a Target Protein
Nucleic Acids Research, 1997Co-Authors: Bernard Hallet, David J Sherratt, Finbarr HayesAbstract:A new insertion method for probing Protein functional organization was developed. The method relies on the random insertion of transposon Tn4430 and subsequent in vitro deletion of the bulk of the transposon after which a 15 bp insertion remains within the Target gene. This results in pentapeptide insertions randomly distributed in the Target Protein. Characterization of 23 pentapeptide insertions in TEM-1 β-lactamase demonstrated the utility of the method. The phenotypes associated with the mutated β-lactamase Proteins equated both with the sorts of local peptide structures in which the pentapeptide insertions occurred and their position in the three-dimensional structure of the enzyme. Linker insertion mutagenesis can provide invaluable insights into Protein structure‐function relationships. However, most linker insertion mutagenesis procedures are technically demanding and are limited to insertions at preexisting restriction enzyme sites ( 1). In this study, a simple and efficient transposon-based linker insertion mutagenesis strategy is described. Transposon Tn4430, a Tn3-related transposon from Bacillus thuringiensis, transposes efficiently in Escherichia coli and duplicates 5 bp of host sequences at the insertion point ( 2, this
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pentapeptide scanning mutagenesis random insertion of a variable five amino acid cassette in a Target Protein
Nucleic Acids Research, 1997Co-Authors: Bernard Hallet, David J Sherratt, Finbarr HayesAbstract:A new insertion method for probing Protein functional organization was developed. The method relies on the random insertion of transposon Tn 4430 and subsequent in vitro deletion of the bulk of the transposon after which a 15 bp insertion remains within the Target gene. This results in pentapeptide insertions randomly distributed in the Target Protein. Characterization of 23 pentapeptide insertions in TEM-1beta-lactamase demonstrated the utility of the method. The phenotypes associated with the mutated beta-lactamase Proteins equated both with the sorts of local peptide structures in which the pentapeptide insertions occurred and their position in the three-dimensional structure of the enzyme.
Takuya Sasaki - One of the best experts on this subject based on the ideXlab platform.
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rabring7 a Target Protein for rab7 small g Protein
Methods in Enzymology, 2005Co-Authors: Kouichi Mizuno, Ayuko Sakane, Takuya SasakiAbstract:Rab7, a member of the Rab family of small G Proteins, has been shown to regulate late endocytic traffic and lysosome biogenesis, but the exact roles and the mode of actions of Rab7 are still undetermined. Accumulating evidence suggests that each Rab Protein has multiple Target Proteins and works together with them to coordinate the individual step of vesicle traffic. Rabring7 (Rab7‐interacting ring finger Protein) is a Rab7 Target Protein that has been isolated using a CytoTrap system. This Protein shows no homology with RILP, which has been reported as another Rab7 Target Protein. Rabring7 is recruited efficiently to late endosome/lysosome by the GTP‐bound form of Rab7. Exogenous expression of Rabring7 not only affects epidermal growth factor degradation but also induces the perinuclear aggregation of lysosomes and the increased acidity in the lysosomes. This chapter describes the procedures for the isolation of Rabring7 with a CytoTrap system, the analysis of the Rab7–Rabring7 interactions, and the properties of Rabring7.
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rabring7 a novel rab7 Target Protein with a ring finger motif
Molecular Biology of the Cell, 2003Co-Authors: Kouichi Mizuno, Akiko Kitamura, Takuya SasakiAbstract:Rab7, a member of the Rab family small G Proteins, has been shown to regulate intracellular vesicle traffic to late endosome/lysosome and lysosome biogenesis, but the exact roles of Rab7 are still undetermined. Accumulating evidence suggests that each Rab Protein has multiple Target Proteins that function in the exocytic/endocytic pathway. We have isolated a new Rab7 Target Protein, Rabring7 (Rab7-interacting RING finger Protein), using a CytoTrap system. It contains an H2 type RING finger motif at the C termini. Rabring7 shows no homology with RILP, which has been reported as another Rab7 Target Protein. GST pull-down and coimmunoprecipitation assays demonstrate that Rabring7 specifically binds the GTP-bound form of Rab7 at the N-terminal portion. Rabring7 is found mainly in the cytosol and is recruited efficiently to late endosomes/ lysosomes by the GTP-bound form of Rab7 in BHK cells. Overexpression of Rabring7 not only affects epidermal growth factor degradation but also causes the perinuclear aggregation of lysosomes, in which the accumulation of the acidotropic probe LysoTracker is remarkably enhanced. These results suggest that Rabring7 plays crucial roles as a Rab7 Target Protein in vesicle traffic to late endosome/lysosome and lysosome biogenesis.
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rabring7 a novel rab7 Target Protein with a ring finger motif
Molecular Biology of the Cell, 2003Co-Authors: Kouichi Mizuno, Akiko Kitamura, Takuya SasakiAbstract:Rab7, a member of the Rab family small G Proteins, has been shown to regulate intracellular vesicle traffic to late endosome/lysosome and lysosome biogenesis, but the exact roles of Rab7 are still ...
Itaru Hamachi - One of the best experts on this subject based on the ideXlab platform.
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affinity guided oxime chemistry for selective Protein acylation in live tissue systems
Journal of the American Chemical Society, 2017Co-Authors: Tomonori Tamura, Zhining Song, Kazuma Amaike, Shin Lee, Sifei Yin, Shigeki Kiyonaka, Itaru HamachiAbstract:Catalyst-mediated Protein modification is a powerful approach for the imaging and engineering of natural Proteins. We have previously developed affinity-guided 4-dimethylaminopyridine (AGD) chemistry as an efficient Protein modification method using a catalytic acyl transfer reaction. However, because of the high electrophilicity of the thioester acyl donor molecule, AGD chemistry suffers from nonspecific reactions to Proteins other than the Target Protein in crude biological environments, such as cell lysates, live cells, and tissue samples. To overcome this shortcoming, we here report a new acyl donor/organocatalyst system that allows more specific and efficient Protein modification. In this method, a highly nucleophilic pyridinium oxime (PyOx) catalyst is conjugated to a ligand specific to the Target Protein. The ligand-tethered PyOx selectively binds to the Target Protein and facilitates the acyl transfer reaction of a mild electrophilic N-acyl-N-alkylsulfonamide acyl donor on the Protein surface. We ...
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disassembly driven turn on fluorescent nanoprobes for selective Protein detection
Journal of the American Chemical Society, 2010Co-Authors: Keigo Mizusawa, Yousuke Takaoka, Shinya Tsukiji, Yoshiyuki Ishida, Masayoshi Miyagawa, Itaru HamachiAbstract:"Switchable" fluorescent probes, which induce changes in the fluorescence properties (e.g., intensity and/or wavelength) only at the intended Target Protein, are particularly useful for selective Protein detection or imaging. However, the strategy for designing such smart probes remains very limited. We report herein a novel mechanism for generating Protein-specific "turn-on" fluorescent probes. Our approach uses an amphiphilic, self-assembling compound consisting of a fluorophore and a Protein ligand. In the absence of Target Protein, the probe forms self-assembled aggregates in aqueous solution and displays almost no fluorescence because of efficient quenching. On the other hand, it emits bright fluorescence in response to the Target Protein through recognition-induced disassembly of the probe. On the basis of this strategy, we successfully developed three types of fluorescent probes that allow the detection of carbonic anhydrase, avidin, and trypsin via turn-on emission signals. It is anticipated that the present supramolecular approach may facilitate the development of new Protein-specific switchable fluorescent probes that are useful for a wide range of applications, such as diagnosis and molecular imaging.
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self assembling nanoprobes that display off on 19f nuclear magnetic resonance signals for Protein detection and imaging
Nature Chemistry, 2009Co-Authors: Yousuke Takaoka, Takashi Sakamoto, Shinya Tsukiji, Michiko Narazaki, Tetsuya Matsuda, Hidehito Tochio, Masahiro Shirakawa, Itaru HamachiAbstract:A 19F magnetic resonance imaging signal from a Protein-specific binding agent can be used to detect the presence of the Target Protein in live cells. The signal is switched off in the absence of Target Protein due to aggregation of the probe into nanoclusters.
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self assembling nanoprobes that display off on 19 f nuclear magnetic resonance signals for Protein detection and imaging
Nature Chemistry, 2009Co-Authors: Yousuke Takaoka, Takashi Sakamoto, Shinya Tsukiji, Michiko Narazaki, Tetsuya Matsuda, Hidehito Tochio, Masahiro Shirakawa, Itaru HamachiAbstract:A 19F magnetic resonance imaging signal from a Protein-specific binding agent can be used to detect the presence of the Target Protein in live cells. The signal is switched off in the absence of Target Protein due to aggregation of the probe into nanoclusters.
Bernard Hallet - One of the best experts on this subject based on the ideXlab platform.
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pentapeptide scanning mutagenesis random insertion of a variable five amino acid cassette in a Target Protein
Nucleic Acids Research, 1997Co-Authors: Bernard Hallet, David J Sherratt, Finbarr HayesAbstract:A new insertion method for probing Protein functional organization was developed. The method relies on the random insertion of transposon Tn4430 and subsequent in vitro deletion of the bulk of the transposon after which a 15 bp insertion remains within the Target gene. This results in pentapeptide insertions randomly distributed in the Target Protein. Characterization of 23 pentapeptide insertions in TEM-1 β-lactamase demonstrated the utility of the method. The phenotypes associated with the mutated β-lactamase Proteins equated both with the sorts of local peptide structures in which the pentapeptide insertions occurred and their position in the three-dimensional structure of the enzyme. Linker insertion mutagenesis can provide invaluable insights into Protein structure‐function relationships. However, most linker insertion mutagenesis procedures are technically demanding and are limited to insertions at preexisting restriction enzyme sites ( 1). In this study, a simple and efficient transposon-based linker insertion mutagenesis strategy is described. Transposon Tn4430, a Tn3-related transposon from Bacillus thuringiensis, transposes efficiently in Escherichia coli and duplicates 5 bp of host sequences at the insertion point ( 2, this
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pentapeptide scanning mutagenesis random insertion of a variable five amino acid cassette in a Target Protein
Nucleic Acids Research, 1997Co-Authors: Bernard Hallet, David J Sherratt, Finbarr HayesAbstract:A new insertion method for probing Protein functional organization was developed. The method relies on the random insertion of transposon Tn 4430 and subsequent in vitro deletion of the bulk of the transposon after which a 15 bp insertion remains within the Target gene. This results in pentapeptide insertions randomly distributed in the Target Protein. Characterization of 23 pentapeptide insertions in TEM-1beta-lactamase demonstrated the utility of the method. The phenotypes associated with the mutated beta-lactamase Proteins equated both with the sorts of local peptide structures in which the pentapeptide insertions occurred and their position in the three-dimensional structure of the enzyme.
