title: Amyloid transition of ubiquitin on silver nanoparticles produced by pulsed laser ablation in liquid as a function of stabilizer and single-point mutations.
abstract: The interaction of nanoparticles with proteins has emerged as a key issue in addressing the problem of nanotoxicity. We investigated the interaction of silver nanoparticles (AgNPs), produced by laser ablation with human ubiquitin (Ub), a protein essential for degradative processes in cells. The surface plasmon resonance peak of AgNPs indicates that Ub is rapidly adsorbed on the AgNP surface yielding a protein corona; the Ub-coated AgNPs then evolve into clusters held together by an amyloid form of the protein, as revealed by binding of thioflavin T fluorescent dye. Transthyretin, an inhibitor of amyloid-type aggregation, impedes aggregate formation and disrupts preformed AgNP clusters. In the presence of sodium citrate, a common stabilizer that confers an overall negative charge to the NPs, Ub is still adsorbed on the AgNP surface, but no clustering is observed. Ub mutants bearing a single mutation at one edge β strand (i.e. Glu16Val) or in loop (Glu18Val) behave in a radically different manner.
authors: Department of Chemistry, University of Bari "Aldo Moro" via Orabona, 4, 70125, Bari (Italy).
authors: Vincenzo
authors: V
authors: Mangini
authors: Marcella
authors: M
authors: Dell'Aglio
authors: Angelo
authors: A
authors: De Stradis
authors: Alessandro
authors: A
authors: De Giacomo
authors: Olga
authors: O
authors: De Pascale
authors: Giovanni
authors: G
authors: Natile
authors: Fabio
authors: F
authors: Arnesano
mesh_terms: D000682:Amyloid / Q000737:chemistry* / Q000378:metabolism; D052160:Benzothiazoles; D002951:Citrates / Q000737:chemistry; D006801:Humans; D007834:Lasers; D053768:Metal Nanoparticles / Q000737:chemistry*; D017354:Point Mutation; D017433:Protein Structure, Secondary; D012834:Silver / Q000737:chemistry*; D000077559:Sodium Citrate; D020349:Surface Plasmon Resonance; D013844:Thiazoles / Q000737:chemistry; D025801:Ubiquitin / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism
chemical_list: D000682:Amyloid; D052160:Benzothiazoles; D002951:Citrates; D013844:Thiazoles; D025801:Ubiquitin; D000077559:Sodium Citrate; C009462:thioflavin T; D012834:Silver
keywords: amyloids; laser ablation; mutagenesis; nanoparticles; ubiquitin