title: Selection of a novel peptide aptamer with high affinity for TiO2-nanoparticle through a direct electroporation with TiO2-binding phage complexes.
abstract: We have developed an easy and rapid screening method of peptide aptamers with high affinity for a target material TiO2using M13 phage-display and panning procedure. In a selection step, the phage-substrate complexes and Escherichia coli cells were directly applied by electric pulse for electroporation, without separating the objective phages from the TiO2nanoparticles. Using this simple and rapid method, we obtained a novel peptide aptamer (named ST-1 with the sequence AYPQKFNNNFMS) with highly strong binding activity for TiO2. A cage-shaped protein fused with both ST-1 and an available carbon nanotube-affinity peptide was designed and produced in E. coli. The multi-functional supraprotein could efficiently mineralize a titanium-compound around the surface of single-wall carbon nanotubes (SWNTs), indicating that the ST-1 is valuable in the fabrication of nano-composite materials with titanium-compounds. The structural analysis of ST-1 variants indicated the importance of the N-terminal region (as a motif of AXPQKX6S) of the aptamer in the TiO2-binding activity.
authors.affiliation: Frontier Research Labs., Institute for Innovation, Ajinomoto Co., Inc., 1-1 Suzuki-cho, Kawasaki-ku, Kawasaki-shi, Kanagawa 210-8681, Japan. Electronic address: ippei_inoue@ajinomoto.com.
authors.forename: Ippei
authors.initials: I
authors.lastname: Inoue
authors.affiliation: Graduate School of Materials Science, Nara Institute of Science and Technology, 8916-5 Takayama, Ikoma, Nara 630-0192, Japan.
authors.forename: Yasuaki
authors.initials: Y
authors.lastname: Ishikawa
authors.affiliation: Graduate School of Materials Science, Nara Institute of Science and Technology, 8916-5 Takayama, Ikoma, Nara 630-0192, Japan.
authors.forename: Yukiharu
authors.initials: Y
authors.lastname: Uraoka
authors.affiliation: Graduate School of Materials Science, Nara Institute of Science and Technology, 8916-5 Takayama, Ikoma, Nara 630-0192, Japan.
authors.forename: Ichiro
authors.initials: I
authors.lastname: Yamashita
authors.affiliation: Frontier Research Labs., Institute for Innovation, Ajinomoto Co., Inc., 1-1 Suzuki-cho, Kawasaki-ku, Kawasaki-shi, Kanagawa 210-8681, Japan.
authors.forename: Hisashi
authors.initials: H
authors.lastname: Yasueda
mesh_terms: D052158:Aptamers, Peptide / Q000737:chemistry / Q000302:isolation & purification*; D001435:Bacteriophages / Q000737:chemistry / Q000235:genetics; D001665:Binding Sites; D061505:Cell Surface Display Techniques / Q000379:methods*; D004396:Coloring Agents / Q000737:chemistry; D018274:Electroporation / Q000379:methods*; D004926:Escherichia coli; D053761:Nanocomposites / Q000737:chemistry; D053758:Nanoparticles / Q000737:chemistry; D037742:Nanotubes, Carbon / Q000737:chemistry; D013379:Substrate Specificity; D014025:Titanium / Q000737:chemistry*
chemical_list: D052158:Aptamers, Peptide; D004396:Coloring Agents; D037742:Nanotubes, Carbon; C009495:titanium dioxide; D014025:Titanium
keywords: Cage-shaped protein; Carbon nanotube; Electroporation; Nanocomposite; Peptide aptamer; Phage display; TiO(2)