title: Self-assembly of a model peptide incorporating a hexa-histidine sequence attached to an oligo-alanine sequence, and binding to gold NTA/nickel nanoparticles.
abstract: Amyloid fibrils are formed by a model surfactant-like peptide (Ala)10-(His)6 containing a hexa-histidine tag. This peptide undergoes a remarkable two-step self-assembly process with two distinct critical aggregation concentrations (cac's), probed by fluorescence techniques. A micromolar range cac is ascribed to the formation of prefibrillar structures, whereas a millimolar range cac is associated with the formation of well-defined but more compact fibrils. We examine the labeling of these model tagged amyloid fibrils using Ni-NTA functionalized gold nanoparticles (Nanogold). Successful labeling is demonstrated via electron microscopy imaging. The specificity of tagging does not disrupt the β-sheet structure of the peptide fibrils. Binding of fibrils and Nanogold is found to influence the circular dichroism associated with the gold nanoparticle plasmon absorption band. These results highlight a new approach to the fabrication of functionalized amyloid fibrils and the creation of peptide/nanoparticle hybrid materials.
authors.affiliation: Department of Chemistry, University of Reading , Whiteknights, Reading RG6 6AD, United Kingdom.
authors.forename: Ian W
authors.initials: IW
authors.lastname: Hamley
authors.forename: Steven
authors.initials: S
authors.lastname: Kirkham
authors.forename: Ashkan
authors.initials: A
authors.lastname: Dehsorkhi
authors.forename: Valeria
authors.initials: V
authors.lastname: Castelletto
authors.forename: Jozef
authors.initials: J
authors.lastname: Adamcik
authors.forename: Raffaele
authors.initials: R
authors.lastname: Mezzenga
authors.forename: Janne
authors.initials: J
authors.lastname: Ruokolainen
authors.forename: Claudia
authors.initials: C
authors.lastname: Mazzuca
authors.forename: Emanuela
authors.initials: E
authors.lastname: Gatto
authors.forename: Mariano
authors.initials: M
authors.lastname: Venanzi
authors.forename: Ernesto
authors.initials: E
authors.lastname: Placidi
authors.forename: Panayiotis
authors.initials: P
authors.lastname: Bilalis
authors.forename: Hermis
authors.initials: H
authors.lastname: Iatrou
mesh_terms: D006046:Gold / Q000737:chemistry*; D006639:Histidine / Q000737:chemistry*; D053768:Metal Nanoparticles / Q000737:chemistry*; D009532:Nickel / Q000737:chemistry*; D010455:Peptides / Q000737:chemistry*
chemical_list: D010455:Peptides; C019529:polyalanine; C033223:polyhistidine; D006639:Histidine; D006046:Gold; D009532:Nickel