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.
Hamley, I., Kirkham, S., Dehsorkhi, A., Castelletto, V., Adamcik, J., Mezzenga, R., et al. (2014). Self-assembly of a model peptide incorporating a hexa-histidine sequence attached to an Oligo-Alanine sequence, and binding to gold NTA/nickel nanoparticles. BIOMACROMOLECULES, 15(9), 3412-3420 [10.1021/bm500950c].
Self-assembly of a model peptide incorporating a hexa-histidine sequence attached to an Oligo-Alanine sequence, and binding to gold NTA/nickel nanoparticles
MAZZUCA, CLAUDIA;GATTO, EMANUELA;VENANZI, MARIANO;
2014-01-01
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.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.