22 results on '"TAKURO NIIDOME"'
Search Results
2. A Solid-in-Oil Dispersion of Gold Nanorods Can Enhance Transdermal Protein Delivery and Skin Vaccination
- Author
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Kenji Kaneko, Yoshiro Tahara, Yoshiki Katayama, Dakrong Pissuwan, Takuro Niidome, Ryohsuke Kurihara, Masahiro Goto, Noriho Kamiya, and Keisuke Nose
- Subjects
Nanotubes ,Materials science ,Nanotechnology ,General Chemistry ,Administration, Cutaneous ,Biomaterials ,Vaccination ,Mice ,Microscopy, Electron, Transmission ,Animals ,General Materials Science ,Nanorod ,Gold ,Dispersion (chemistry) ,Skin ,Biotechnology ,Transdermal - Published
- 2010
3. Inflammatory cell-specific transgene expression system responding to Iκ-B kinase beta activation
- Author
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Takuro Niidome, Hideki Nakashima, Jeong Hun Kang, Takeshi Mori, Daisuke Asai, Yoshiki Katayama, Kenji Kawamura, Yoko Shoji, Akira Tsuchiya, and Jun Oishi
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Cell signaling ,Genetic enhancement ,Transgene ,Gene Expression ,Biology ,Gene delivery ,Mice ,Drug Discovery ,Gene expression ,Genetics ,Animals ,Humans ,Electrophoretic mobility shift assay ,Transgenes ,Molecular Biology ,Genetics (clinical) ,Inflammation ,Molecular Structure ,Kinase ,Gene Transfer Techniques ,Genetic Therapy ,Molecular biology ,I-kappa B Kinase ,Enzyme Activation ,Molecular Medicine ,Peptides ,Intracellular - Abstract
Background Control of inflammation is essential for the clinical management of many common human diseases. However, there are few generally applicable strategies to convert an abnormal intracellular signal into a gene expression that leads to normalization of the intracellular environment. Recently, we proposed a novel strategy termed D-RECS (i.e. drug or gene delivery system responding to cellular signals) to convert an intracellular signal to transgene expression. In the present study, we applied this concept to inflammatory cells using Iκ-B kinase as a signal molecule that triggers the gene expression. Methods Candidate cationic substrates of Iκ-B kinase (IKK)β were synthesized and their reactivity was investigated. Then, polymers grafted with these peptides were prepared by radical polymerization. Polymer/DNA complexes (polyplexes) were prepared by mixing plasmid DNAs with the polymers. The behaviour of these polyplexes by adding IKKβ was examined. Furthermore, changes of gene expression were evaluated after the microinjection of polyplex into living cells under conditions of nuclear factor (NF)-κB activation. Results Synthetic peptides with additional lysine residues were well phosphorylated by IKKβ. Both the polymer and the polyplex were also phosphorylated by IKKβ. The results of gel shift assay showed that the polyplex was disintegrated and free DNA was released in the presence of IKKβ. The polyplex comprising-green fluorescent protein plasmid DNA and the polymer expressed the transgene in living cells exposed to a pro-inflammatory stimulus. Conclusions Our concept of cell-specific gene expression was demonstrated to work in inflammatory cells. This method may provide a unique strategy for gene therapy exclusively in inflammatory cells. Copyright © 2009 John Wiley & Sons, Ltd.
- Published
- 2009
4. Interaction of lipophilic peptides derived from mastoparan with phospholipid vesicles
- Author
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Haruhiko Aoyagi, Kinya Okamoto, Naoya Ohmori, Hisakazu Mihara, Rie Kawakami, and Takuro Niidome
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Phospholipid vesicles ,1,2-Dipalmitoylphosphatidylcholine ,Acylation ,Phospholipid ,Wasp Venoms ,Peptide ,Hemolysis ,Biochemistry ,Protein Structure, Secondary ,Membrane Lipids ,Structure-Activity Relationship ,chemistry.chemical_compound ,Endocrinology ,medicine ,Phospholipids ,chemistry.chemical_classification ,Circular Dichroism ,Phosphatidylglycerols ,medicine.disease ,Membrane ,chemistry ,Drug Design ,Acyl chain ,Mastoparan ,Liposomes ,Intercellular Signaling Peptides and Proteins ,lipids (amino acids, peptides, and proteins) ,Peptides - Abstract
Various kinds of lipophilic peptides were prepared by acylation of an alpha-helical peptide, mastoparan, to investigate the effects of acyl groups on the interaction of peptides with phospholipid membranes. alpha-Helicity of the peptides was increased by introduction of long acyl groups. Acyl peptides showed different membrane-perturbation activities for neutral and acidic phospholipid vesicles, whereas a peptide with a dialkycarbamoyl group always exhibited a strong activity. High hemolytic activities were observed for the peptides with long acyls (single or double chain). These results indicate that lipophilic groups introduced to mastoparan contribute greatly to the interaction of the peptide with phospholipid membranes with lengthening of the acyl chain and that the structural character of the lipophilic group also influences the conformation of the peptide.
- Published
- 2009
5. Interaction of α-helical peptides with phospholipid membrane: effects of chain length and hydrophobicity of peptides
- Author
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Tomomitsu Hatakeyama, Takuro Niidome, Naoya Ohmori, Haruhiko Aoyagi, and Hisakazu Mihara
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Staphylococcus aureus ,Circular dichroism ,1,2-Dipalmitoylphosphatidylcholine ,Chemical Phenomena ,Phospholipid ,Peptide ,Hemolysis ,Membrane Fusion ,Biochemistry ,Protein Structure, Secondary ,Structure-Activity Relationship ,chemistry.chemical_compound ,Endocrinology ,Protein structure ,Escherichia coli ,Proteus vulgaris ,Amino Acid Sequence ,Peptide sequence ,Phospholipids ,chemistry.chemical_classification ,Chemistry, Physical ,Circular Dichroism ,Vesicle ,Lipid bilayer fusion ,Phosphatidylglycerols ,Spectrometry, Fluorescence ,Membrane ,chemistry ,Liposomes ,Biophysics ,Peptides ,Bacillus subtilis - Abstract
To investigate the interaction of amphiphilic alpha-helical peptides with phospholipid membranes, we synthesized Ac-(Leu-Ala-Arg-Leu)3-NHCH3 (4[3]) and three derivatives, in which the chain length and the size of the hydrophobic region of the peptides were different from each other. These peptides formed an alpha-helical structure in the presence of vesicles. In the membrane-perturbation measurement, only 43 showed a strong membrane-perturbation activity below phase-transition temperature (25 degrees C), but above phase-transition temperature (50 degrees C), most peptides showed similar strong activities. On the other hand, in membrane-fusion measurement the long peptides, e.g., Ac-(Leu-Ala-Arg-Leu)3-(Leu-Arg-Ala-Leu)3-NHCH3, had strong activities at low peptide concentrations at 25 degrees C. The present study indicated a parallel relationship did not always exist between membrane fusion and perturbation caused by peptides.
- Published
- 2009
6. Measurement of Homogeneous Kinase Activity for Cell Lysates Based on the Aggregation of Gold Nanoparticles
- Author
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Jeong Hun Kang, Takeshi Mori, Yoji Asami, Miharu Tanabe, Yoshiki Katayama, Jun Oishi, and Takuro Niidome
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Cell Extracts ,Cell lysates ,chemistry.chemical_classification ,Surface Properties ,Chemistry ,Drug discovery ,High-throughput screening ,Organic Chemistry ,Metal Nanoparticles ,Biochemistry ,Cell Line ,Cell biology ,Enzyme Activation ,Enzyme ,Colloidal gold ,Homogeneous ,Molecular Medicine ,Gold ,Kinase activity ,Protein Kinases ,Molecular Biology - Published
- 2007
7. Peptide vector for gene delivery with high affinity for phosphatidylserine
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Kanako Nishimura, Yoshiki Katayama, Yasushi Taguchi, Kazutoshi Kobayashi, Shinichi Kuriyama, Kazutoshi Yanagibashi, Kiyoshi Mizuguchi, and Takuro Niidome
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Genetic Vectors ,Molecular Sequence Data ,Peptide ,Phosphatidylserines ,Biology ,Gene delivery ,Transfection ,Biochemistry ,Cell membrane ,chemistry.chemical_compound ,Structural Biology ,Chlorocebus aethiops ,Drug Discovery ,medicine ,Animals ,A-DNA ,Amino Acid Sequence ,Vector (molecular biology) ,Vero Cells ,Molecular Biology ,Pharmacology ,chemistry.chemical_classification ,Factor VIII ,Circular Dichroism ,Organic Chemistry ,Gene Transfer Techniques ,DNA ,General Medicine ,Phosphatidylserine ,Protein Structure, Tertiary ,Membrane ,medicine.anatomical_structure ,chemistry ,Liposomes ,Biophysics ,Molecular Medicine ,Peptides ,Plasmids - Abstract
Since phosphatidylserine (PS) is known to translocate to the external face of the plasma membrane when the cell membrane becomes disordered, we decided to focus our attention on PS as a target molecule for gene delivery. In this paper, the novel peptide Td3701 was designed, synthesized, and characterized for its physico-chemico-biological properties. Td3701 simultaneously exhibited both characters as a DNA carrier and a sensor probe for active targeting, which seemed to be triggered by structural changes in the presence of PS. This is a very unique character among nonviral vectors, and it is believed that Td3701 could be used for selective gene delivery. Copyright © 2006 European Peptide Society and John Wiley & Sons, Ltd.
- Published
- 2006
8. Parallel and antiparallel dimers of magainin 2: their interaction with phospholipid membrane and antibacterial activity
- Author
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Haruhiko Aoyagi, Tomomitsu Hatekeyama, Yuko Matsushita, Takuro Niidome, and Yasuhiro Mukai
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Circular dichroism ,Cell Membrane Permeability ,Membrane permeability ,Stereochemistry ,Molecular Sequence Data ,Phospholipid ,Peptide ,Xenopus Proteins ,Magainins ,Antiparallel (biochemistry) ,Biochemistry ,chemistry.chemical_compound ,Structural Biology ,Drug Discovery ,Amino Acid Sequence ,Molecular Biology ,Phospholipids ,Pharmacology ,chemistry.chemical_classification ,Liposome ,Bacteria ,Chemistry ,Circular Dichroism ,Organic Chemistry ,Magainin ,General Medicine ,Anti-Bacterial Agents ,Protein Transport ,Spectrometry, Fluorescence ,Membrane ,Molecular Medicine ,Dimerization ,Antimicrobial Cationic Peptides - Abstract
Magainin 2 (M2) forms pores by associating with several other M2 molecules in lipid membranes and shows antibacterial activity. To examine the effect of M2 dimerization on biological activity and membrane interaction, parallel and antiparallel M2 dimers were prepared from two monomeric precursors. Antibacterial and haemolytic activities were enhanced by dimerization. CD measurements showed that both dimers and monomers have an α-helical structure in the presence of lipid vesicles. Tryptophan fluorescence shift and KI quenching studies showed that all the peptides were more deeply embedded in acidic liposomes than in neutral liposomes. Experiments on dye-leakage activity and membrane translocation of peptides suggest that dimers and monomers form pores through lipid membranes, although the pore formation may be accompanied by membrane disturbance. Although dimerization of M2 increased the interaction activity with lipid membranes, no appreciable difference between the activities of parallel and antiparallel M2 dimers was observed. Copyright © 2002 European Peptide Society and John Wiley & Sons, Ltd.
- Published
- 2002
9. Interaction of pleurocidin and its analogs with phospholipid membrane and their antibacterial activity
- Author
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Tomomitsu Hatakeyama, Yasuhiro Mukai, Kazutoshi Yoshida, Haruhiko Aoyagi, C. Takashi, Takuro Niidome, and Yoko Tokunaga
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chemistry.chemical_classification ,Vesicle ,Magainin ,Phospholipid ,Peptide ,Biological activity ,Biochemistry ,chemistry.chemical_compound ,Endocrinology ,chemistry ,Pleurocidin ,Antibacterial activity ,Lipid bilayer - Abstract
A 25-mer cationic peptide pleurocidin, isolated from the winter flounder, has broad antibacterial activity. To clarify the structure-activity relationship, its properties and biological activity were examined. CD measurements showed that pleurocidin took an alpha-helical structure in the presence of DOPC/DOPG (3:1, anionic) vesicles. Very weak hemolytic activity of pleurocidin was observed and its antibacterial activity was moderate. Tryptophan fluorescence shift measurements showed that pleurocidin interacted weakly with a neutral phospholipid, but strongly with an acidic phospholipid. The peptide exhibited weak dye-leakage activity for DOPC (neutral) vesicles and moderate activity for acidic vesicles. From experiments on dye-leakage activity and membrane translocation of the peptide, it seemed likely that pleurocidin, like magainin 2, forms pores in the lipid membrane. A study of amino acid substitution in pleurocidin revealed that alpha-helicity, rather than hydrophobicity, affects the properties and activity of the peptide.
- Published
- 2001
10. Interaction of mastoparan with membranes studied by1H-NMR spectroscopy in detergent micelles and by solid-state2H-NMR and15N-NMR spectroscopy in oriented lipid bilayers
- Author
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Mitsuo Iwadate, Haruhiko Aoyagi, Takuro Niidome, Anne S. Ulrich, Makoto Demura, Tetsuo Asakura, and Yumiko Hori
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Crystallography ,Chemistry ,Bilayer ,Chemical shift ,Mastoparan ,Helix ,Analytical chemistry ,Nuclear magnetic resonance spectroscopy ,Lipid bilayer ,complex mixtures ,Biochemistry ,Two-dimensional nuclear magnetic resonance spectroscopy ,Micelle - Abstract
Several complementary NMR approaches were used to study the interaction of mastoparan, a 14-residue peptide toxin from wasp venom, with lipid membranes. First, the 3D structure of mastoparan was determined using 1H-NMR spectroscopy in perdeuterated (SDS-d25) micelles. NOESY experiments and distance geometry calculations yielded a straight amphiphilic α-helix with high-order parameters, and the chemical shifts of the amide protons showed a characteristic periodicity of 3–4 residues. Secondly, solid-state 2H-NMR spectoscopy was used to describe the binding of mastoparan to lipid bilayers, composed of headgroup-deuterated dimyristoylglycerophosphocholine (DMPC-d4) and dimyristoylphosphatidylglycerol (DMPG). By correlating the deuterium quadrupole splittings of the α-segments and β-segments, it was possible to differentiate the electrostatically induced structural response of the choline headgroup from dynamic effects induced by the peptide. A partial phase separation was observed, leading to a DMPG-rich phase and a DMPG-depleted phase, each containing some mastoparan. Finally, the insertion and orientation of a specifically 15N-labeled mastoparan (at position Ala10) in the bilayer environment was investigated by solid-state 15N-NMR spectroscopy, using macroscopically oriented samples. Two distinct orientational states were observed for the mastoparan helix, namely an in-plane and a trans-membrane alignment. The two populations of 90% in-plane and 10% trans-membrane helices are characterized by a mosaic spread of ± 30° and ± 10°, respectively. The biological activity of mastoparan is discussed in terms of a pore-forming model, as the peptide is known to be able to induce nonlamellar phases and facilitate a flip-flop between the monolayers.
- Published
- 2001
11. Antibacterial activity of bactenecin 5 fragments and their interaction with phospholipid membranes
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Tomomitsu Hatakeyama, Haruhiko Aoyagi, Takuro Niidome, and Yoko Tokunaga
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Circular dichroism ,Stereochemistry ,Lipid Bilayers ,Phospholipid ,Peptide ,Arginine ,Hemolysis ,Membrane Fusion ,Peptides, Cyclic ,Biochemistry ,Structure-Activity Relationship ,chemistry.chemical_compound ,Structural Biology ,Drug Discovery ,Animals ,Amino Acid Sequence ,Molecular Biology ,Phospholipids ,Polyproline helix ,Pharmacology ,chemistry.chemical_classification ,Bactenecin ,Circular Dichroism ,Organic Chemistry ,Amino acid substitution ,General Medicine ,Fluoresceins ,Peptide Fragments ,Anti-Bacterial Agents ,Molecular Weight ,Membrane ,chemistry ,Liposomes ,Molecular Medicine ,Cattle ,Antibacterial activity - Abstract
Bactenecin 5 (Bac 5) is an antibacterial 43mer peptide isolated from bovine neutrophils. It consists of an Arg-rich N-terminal region and successive repeats of Arg-Pro-Pro-Ile (or Phe). We synthesized Bac 51-23 and several related peptides to clarify the roles these regions play in antibacterial activity. An assay of antibacterial activity revealed that such activity requires the presence of Arg residues at or near the N-terminus, as well as a chain length exceeding 15 residues. None of the peptides exhibited haemolytic activity. Polyproline II-like CD curves were observed for most of the peptides. Measurements of the membrane perturbation and fusion indicated that the perturbation and fusogenic activities of the peptides were, generally, parallel to their antibacterial activities. Amino acid substitution in the repeating region had some effect on antibacterial activity. Copyright © 2001 European Peptide Society and John Wiley & Sons, Ltd.
- Published
- 2001
12. Required structure of cationic peptide for oligonucleotide-binding and -delivering into cells
- Author
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Haruhiko Aoyagi, Takuro Niidome, Akihiro Wada, Masato Wakamatsu, and Toshiya Hirayama
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Pharmacology ,chemistry.chemical_classification ,Chemistry ,Oligonucleotide ,Stereochemistry ,Organic Chemistry ,Cationic polymerization ,Peptide ,General Medicine ,Biochemistry ,Structural Biology ,Drug Discovery ,Molecular Medicine ,Molecular Biology - Published
- 2000
13. Influence of lipophilic groups in cationic α-helical peptides on their abilities to bind with DNA and deliver genes into cells
- Author
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Y. Matsuo, Takuro Niidome, Mamiko Urakawa, Toshiya Hirayama, Akihiro Wada, Naoya Ohmori, Haruhiko Aoyagi, and Keiko Takaji
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chemistry.chemical_classification ,Conformational change ,Peptide ,Transfection ,Biology ,Biochemistry ,chemistry.chemical_compound ,Endocrinology ,chemistry ,Mastoparan ,Amphiphile ,Gene ,Acyl group ,DNA - Abstract
For the purpose of achieving gene transfer into cells mediated by peptides with a short chain length, we employed two kinds of amphiphilic alpha-helix peptides, mastoparan (INLK-ALAA-LAKK-IL-NH2) obtained from wasp venom and an alpha-helix model peptide (LARL-LARL-LARL-NH2). Furthermore, to strengthen the hydrophobicity of the peptide required for the formation of the aggregates with the DNA, we modified these peptides using several lipophilic groups, i.e. acyl groups with a single chain, a dialkylcarbamoyl group and a cholesteryloxycarbonyl group. We examined the ability of the peptides and their derivatives to bind and aggregate with plasmid DNA, the structural change in the peptides caused by binding with the DNA and the in vitro gene transfer abilities into COS-7 cells. As a result, mastoparan was found to acquire the DNA binding ability by introduction of the lipophilic group. The conformational change in the peptides depended on the hydrophobicity of the introduced acyl group. The DNA complex of most lipophilic mastoparan derivatives could be incorporated into the cells via the endocytosis pathway. In the case of the helix model peptide, the acyl group with a moderate chain length was required for the formation of the aggregate which is competent for incorporation into the cells. In this study, we succeeded in giving such short peptides sufficient gene transfer ability by modifying them with some lipophilic groups. However, the influence of the modification by the lipophilic groups on the formation of aggregates with DNA and the gene transfer ability depended on the structure of the peptide portion. These results indicate that consideration of total hydrophobicity balance is needed for the design of an efficient gene carrier peptide.
- Published
- 1999
14. Interaction of bundled Ser-rich amphiphilic peptides with phospholipid membranes
- Author
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Kazutoshi Yoshida, Yasuhiro Mukai, Tomomitsu Hatakeyama, Naoya Ohmori, Haruhiko Aoyagi, and Takuro Niidome
- Subjects
Staphylococcus aureus ,Circular dichroism ,Molecular Sequence Data ,Phospholipid ,Peptide ,Microbial Sensitivity Tests ,Membrane Fusion ,Biochemistry ,Protein Structure, Secondary ,chemistry.chemical_compound ,Structural Biology ,Drug Discovery ,Amphiphile ,Serine ,Amino Acid Sequence ,Molecular Biology ,Phospholipids ,Pharmacology ,chemistry.chemical_classification ,Chromatography ,Chemistry ,Circular Dichroism ,Vesicle ,Organic Chemistry ,Membranes, Artificial ,General Medicine ,Buffer solution ,Anti-Bacterial Agents ,Spectrometry, Fluorescence ,Membrane ,Biophysics ,Molecular Medicine ,lipids (amino acids, peptides, and proteins) ,Peptides ,Bacillus subtilis ,Membrane Fusion Activity - Abstract
To investigate properties of hydrophilic bundled peptides and their interactions with phospholipid membranes, bundled peptides named [Trp2]- and [Trp12]-4alpha-46S9, which are composed of four fragments of amphiphilic 24-mer peptide, were designed and synthesized. Tryptophan (Trp) was introduced at the 2nd position from the N-terminal or at the centre (12th) of the helix to monitor the peptide-lipid interaction. Circular dichroism measurements indicated that the peptides had low alpha-helicities in a buffer solution (pH 7.4) and also in the presence of dipalmitoyl-DL-3-phosphatidylcholine (DPPC) vesicles. In the presence of DPPC/dipalmitoyl-DL-3-phosphatidylglycerol (DPPG) (3:1) vesicles, the measurement could not be taken because of turbidity induced by vesicle aggregation. Both peptides had moderate perturbation activity for both the neutral and acidic vesicles at 25 degrees C. The perturbation patterns at 50 degrees C were much different from those at 25 degrees C and the maximum activity reached 100% at a low peptide concentration. The results of the measurement of membrane fusion activity of peptides showed a similar tendency to that found in the perturbation experiment. A quenching experiment indicated that the Trp2 and Trp12 residues in [Trp2]- and [Trp12]-4alpha-46S9 were scarcely embedded in neutral lipid membranes.
- Published
- 1999
15. Orientational behavior of phospholipid membranes with mastoparan studied by 31 P solid state NMR
- Author
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Haruhiko Aoyagi, Makoto Demura, Yumiko Hori, Takuro Niidome, and Tetsuo Asakura
- Subjects
Magnetic Resonance Spectroscopy ,Lipid Bilayers ,Biophysics ,Phospholipid ,Membrane orientation ,Wasp Venoms ,Peptide ,Biochemistry ,Nuclear magnetic resonance ,chemistry.chemical_compound ,Non-lamellar phase ,Structural Biology ,Genetics ,Animals ,Lamellar structure ,Amino Acid Sequence ,Anisotropy ,Lipid bilayer ,Molecular Biology ,chemistry.chemical_classification ,Mastoparan ,Phosphatidylglycerols ,Phosphorus ,Cell Biology ,Crystallography ,Membrane ,chemistry ,Solid-state nuclear magnetic resonance ,Intercellular Signaling Peptides and Proteins ,lipids (amino acids, peptides, and proteins) ,Dimyristoylphosphatidylcholine ,Peptides - Abstract
Solid state 31P NMR spectroscopy was used to study the perturbing effect of the wasp venom peptide mastoparan (MP) on lipid bilayers composed of dimyristoylphosphatidylcholine (DMPC) and dimyristoylphosphatidylglycerol (DMPG). The 31P chemical shift anisotropy of multilamellar vesicles decreased with increasing peptide concentration, indicating that MP interacts strongly and selectively with the charged DMPG head group. Macroscopically oriented MP-lipid samples between glass plates were studied by 31P NMR as a function of tilt angle. These spectra showed the coexistence of orientation-dependent lamellar signals as well as an isotropic peak, suggesting that MP can induce non-lamellar phases in DMPC/DMPG membranes.
- Published
- 1999
16. Effect of amino acid substitution in amphiphilic α-helical peptides on peptide-phospholipid membrane interaction
- Author
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Shingo Anzai, Tomomitsu Hatakeyama, Masaaki Nakahara, Yoko Tokunaga, Junko Sonoda, Takuro Niidome, and Haruhiko Aoyagi
- Subjects
Pharmacology ,chemistry.chemical_classification ,Circular dichroism ,Stereochemistry ,Organic Chemistry ,Phospholipid ,Cationic polymerization ,Peptide ,General Medicine ,Biochemistry ,Peptide Conformation ,chemistry.chemical_compound ,Membrane ,chemistry ,Structural Biology ,Drug Discovery ,Amphiphile ,Molecular Medicine ,Antibacterial activity ,Molecular Biology - Abstract
It was previously found that a cationic amphiphilic peptide, Ac-(Leu-Ala-Arg-Leu)3-NHCH3 (4(3)), caused the destabilization of a phospholipid membrane and showed strong antibacterial activity [Lee et al. Biochim. Biophys. Acta 1986; 862: 211-219]. In order to investigate the effect of changing alpha-helix propensity, hydrophobicity and basicity in 4(3) on the peptide conformation and activity, the 4(3) analogs, [Gly (or Val)6]4(3), [Gly (or Val)2,6]4(3), [Gly (or Val)2,6,10]4(3), [Gln3]4(3), [Gln3,7]4(3) and [Gln3,7,11]4(3) were synthesized. Except for [Val2,6]4(3) and [Val2,6,10]4(3), which mainly formed a beta-structure, other peptides formed an alpha-helix and showed moderate membrane-perturbing activity toward neutral and acidic lipid vesicles. All the peptides other than [Val2,6,10]4(3) and [Gln3,7,10]4(3) had the antibacterial activity comparable with that of 4(3). The relationship between the membrane-perturbing activity and the antibacterial activity was not always parallel. Conclusively, the Ala-->Val substitution in 4(3) causes the change of peptide conformation and the presence of a cationic amino acid residue is necessary for the antibacterial activity.
- Published
- 1999
17. Small-angle X-ray scattering study on CEL-III, a hemolytic lectin from HolothuroideaCucumaria echinata, and its oligomer induced by the binding of specific carbohydrate
- Author
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Tomomitsu Hatakeyama, Haruhiko Aoyagi, Hiromiki Kuwahara, Takuro Niidome, Tetsuro Fujisawa, and Yasuaki Hiromasa
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Models, Molecular ,Carbohydrate-binding protein ,Protein Conformation ,Sea Cucumbers ,Hemolysin ,Biophysics ,Lactose ,Biochemistry ,Oligomer ,Hemolysin Proteins ,chemistry.chemical_compound ,Structural Biology ,Lectins ,Genetics ,Animals ,Scattering, Radiation ,Molecular Biology ,Polyacrylamide gel electrophoresis ,Gel electrophoresis ,Molecular mass ,Scattering ,Small-angle X-ray scattering ,X-Rays ,Cell Biology ,Hydrogen-Ion Concentration ,Molecular Weight ,Crystallography ,Monomer ,chemistry ,Radius of gyration ,Electrophoresis, Polyacrylamide Gel ,Toxin ,Lectin ,Protein Binding - Abstract
Hemolytic lectin CEL-III from a marine invertebrate Cucumaria echinata forms an oligomer upon binding of specific carbohydrate such as lactose at high pH values and in the presence of high concentrations of salt. In this study, using small-angle X-ray scattering, we characterized CEL-III and its oligomer induced by the binding of lactose. The molecular mass of the oligomer was determined as 1019 kDa from its forward scattering value, compared with 47 490 Da for the monomer. This oligomer size is much larger than that estimated using SDS–polyacrylamide gel electrophoresis (SDS-PAGE, 270 kDa). The monomer has a 24.6 A radius of gyration and can be approximated by a rod which has a 20 A radius and a height of 75 A, while the oligomer has a 101.4A radius of gyration. Together with the comparison of the radii of gyration and the forward scattering of the cross-section of the monomer and oligomer, it is suggested that in aqueous solution the oligomer comprises three or four molecules of a smaller unit which was observed by SDS-PAGE (270 kDa), held by a relatively weak interaction. The scattering profile also suggests that the oligomer has a hole in its central axis which might be associated with the formation of ion-permeable pores in the erythrocyte membrane by CEL-III during the hemolytic process.
- Published
- 1997
18. ChemInform Abstract: Theragnostic Approaches Using Gold Nanorods and Near Infrared Light
- Author
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Yasuyuki Akiyama, Yasuro Niidome, Takuro Niidome, Akira Ohga, Atsushi Shiotani, Keisuke Nose, and Dakrong Pissuwan
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medicine.anatomical_structure ,Chemistry ,Colloidal gold ,Surface plasmon ,Drug delivery ,Photothermal effect ,Stratum corneum ,medicine ,Nanorod ,Nanotechnology ,General Medicine ,Irradiation ,Photothermal therapy - Abstract
Gold nanoparticles have unique optical properties such as surface-plasmon and photothermal effects. Such properties have resulted in gold nanoparticles having several clinical applications. Gold nanorods (which are rod-shaped gold nanoparticles) show a surface plasmon band in the near-infrared region. They have therefore been proposed as contrast agents for bioimaging, or as heating devices for photothermal therapy. Polyethylene glycol-modified gold nanorods systemically administrated into mice can be detected with integrating sphere, and the stability of the gold nanorods in blood flow evaluated. After intravenous injection of gold nanorods followed by near-infrared laser irradiation, significant tumor damage triggered by the photothermal effect was observed. To deliver gold nanorods to the target tissue, thermosensitive polymer gel-coated gold nanorods were prepared. After intravenous injection of the gel-modified gold nanorods and irradiation of the tumor, a larger amount of gold was detected in the irradiated tumor than in the non-irradiated tumor. This effect is due to the hydrophobic interaction between the cellular membrane or the extracellular matrix and the gel surfaces induced by the photothermal effect. Furthermore, the photothermal effect enhanced the permeability of the stratum corneum of the skin. As a result of treatment of the skin with ovalbumin and gold nanorods followed by near-infrared light irradiation, a significant amount of protein was detected in the skin. The gold nanorods therefore showed several functions as a photothermal nanodevice for bioimaging, thermal therapy, and a drug delivery system.
- Published
- 2011
19. ChemInform Abstract: Efficient Preparation of Cyclic Peptide Mixtures by Solid Phase Synthesis and Cyclization Cleavage with Oxime Resin
- Author
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Haruhiko Aoyagi, Takuro Niidome, Hisakazu Mihara, Hiromichi Kumagai, and Shinji Yamabe
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body regions ,chemistry.chemical_classification ,stomatognathic diseases ,chemistry.chemical_compound ,Solid-phase synthesis ,Chemistry ,General Medicine ,Cleavage (embryo) ,Oxime ,Combinatorial chemistry ,eye diseases ,Cyclic peptide - Abstract
A mixture of cyclic peptides, cyclo(-Arg-Gly-Asp-Xaa-Aca-) (Xaa, 10 amino aids; Aca, e-aminocaproic acid), and another mixture of related peptides were efficiently synthesized by the solid-phase synthesis and cyclization-cleavage method with oxime resin.
- Published
- 2010
20. ChemInform Abstract: Synthesis of Protected Peptides Containing Phosphoserine with Oxime Resin
- Author
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Haruhiko Aoyagi, Hisakazu Mihara, Hiromiki Kuwahara, Takuro Niidome, and Hiroshi Kanegae
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chemistry.chemical_classification ,chemistry.chemical_compound ,Chemistry ,Stereochemistry ,Phosphopeptide ,Phosphoserine ,Molecule ,Peptide ,General Medicine ,Oxime ,Amino acid - Abstract
A protected peptide containing phosphoserine was successfully synthesized by the solid-phase method using the oxime resin. The protected phosphopeptide was utilized to further elongation to a longer peptide and conjugation to a template molecule.
- Published
- 2010
21. ChemInform Abstract: Peptide Synthesis Mediated by Thiolsubtilisin Using Peptide Thioester as Building Block
- Author
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Satoko Ueno, Takuro Niidome, Saburo Aimoto, Ryo Kurosaki, Hisakazu Mihara, Shuko Maeda, Hironobu Hojo, Haruhiko Aoyagi, and Seiji Sakamoto
- Subjects
chemistry.chemical_classification ,Protease ,Stereochemistry ,medicine.medical_treatment ,Peptide ,General Medicine ,Thioester ,Amino acid ,Thiolsubtilisin ,chemistry.chemical_compound ,chemistry ,Peptide synthesis ,medicine ,lipids (amino acids, peptides, and proteins) - Abstract
Peptides were efficiently synthesized by the catalysis of chemically engineered protease, thiolsubtilisin, with peptide thioesters as substrate building blocks. The ligation method was successfully...
- Published
- 2010
22. Required structure of cationic peptide for oligonucleotide-binding and -delivering into cells
- Author
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Akihiro Wada, Toshiya Hirayama, Masato Wakamatsu, Haruhiko Aoyagi, and Takuro Niidome
- Subjects
Cell Survival ,government.form_of_government ,Genetic Vectors ,Cell ,Oligonucleotides ,Peptide ,Transfection ,Biochemistry ,Mass Spectrometry ,Structural Biology ,Cations ,Drug Discovery ,Amphiphile ,medicine ,Animals ,Amino Acids ,Molecular Biology ,Pharmacology ,chemistry.chemical_classification ,Antisense therapy ,Oligonucleotide ,Circular Dichroism ,Organic Chemistry ,Gene Transfer Techniques ,Cationic polymerization ,DNA ,General Medicine ,Amino acid ,Microscopy, Electron ,Binding ability ,medicine.anatomical_structure ,chemistry ,COS Cells ,government ,Molecular Medicine ,Peptides ,Plasmids ,Protein Binding - Abstract
Improvement of the methods for oligonucleotide delivery into cells is necessary for the development of antisense therapy. In the present work, a new strategy for oligonucleotide delivery into cells was tested using cationic peptides as a vector. At first, to understand what structure of the peptide is required for binding with an oligonucleotide, several kinds of alpha-helical and non-alpha-helical peptides containing cationic amino acids were employed. As a result, the amphiphilic alpha-helix peptides were best for binding with the oligonucleotide, and the long chain length and large hydrophobic region in the amphiphilic structure of the peptide were necessary for the binding and forming of aggregates with the oligonucleotide. In the case of non-alpha-helical peptides, no significant binding ability was observed even if their chain lengths and number of cationic amino acid residues were equal to those of the alpha-helical peptides. The remarkable ability of oligonucleotide delivery into COS-7 cells was observed in the alpha-helical peptides with a long chain length and large hydrophobic region in the amphiphilic structure, but was not observed in the non-alpha-helical peptides. It is considered that such alpha-helical peptides could form optimum aggregates with the ODN for uptake into cells. Based on these results, the alpha-helical peptide with a long chain length and large hydrophobic region is applicable as a vector for the delivery of oligonucleotides into cells.
- Published
- 2000
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