title: Designed Modular Proteins as Scaffolds To Stabilize Fluorescent Nanoclusters.
abstract: Proteins have been used as templates to stabilize fluorescent metal nanoclusters thus obtaining stable fluorescent structures, and their fluorescent properties being modulated by the type of protein employed. Designed consensus tetratricopeptide repeat (CTPR) proteins are suited candidates as templates for the stabilization of metal nanoclusters due to their modular structural and functional properties. Here, we have studied the ability of CTPR proteins to stabilize fluorescent gold nanoclusters giving rise to designed functional hybrid nanostructures. First, we have investigated the influence of the number of CTPR units, as well as the presence of cysteine residues in the CTPR protein, on the fluorescent properties of the protein-stabilized gold nanoclusters. Synthetic protocols to retain the protein structure and function have been developed, since the structural and functional integrity of the protein template is critical for further applications. Finally, as a proof-of-concept, a CTPR module with specific binding capabilities has been used to stabilize gold nanoclusters with positive results. Remarkably, the protein-stabilized gold nanocluster obtained combines both the fluorescence properties of the nanoclusters and the functional properties of the protein. The fluorescence changes in nanoclusters fluorescence have been successfully used as a sensor to detect when the specific ligand was recognized by the CTPR module.
authors.affiliation: IMDEA-Nanociencia , Campus de Cantoblanco, 28049 Madrid, Spain.|Centro Nacional de Biotecnología (CNB-CSIC) - IMDEA Nanociencia Associated Unit , Campus de Cantoblanco, 28049 Madrid, Spain.
authors.forename: Pierre
authors.initials: P
authors.lastname: Couleaud
authors.affiliation: IMDEA-Nanociencia , Campus de Cantoblanco, 28049 Madrid, Spain.
authors.forename: Sergio
authors.initials: S
authors.lastname: Adan-Bermudez
authors.affiliation: IMDEA-Nanociencia , Campus de Cantoblanco, 28049 Madrid, Spain.
authors.forename: Antonio
authors.initials: A
authors.lastname: Aires
authors.affiliation: IMDEA-Nanociencia , Campus de Cantoblanco, 28049 Madrid, Spain.|Centro Nacional de Biotecnología (CNB-CSIC) - IMDEA Nanociencia Associated Unit , Campus de Cantoblanco, 28049 Madrid, Spain.
authors.forename: Sara H
authors.initials: SH
authors.lastname: Mejías
authors.affiliation: IMDEA-Nanociencia , Campus de Cantoblanco, 28049 Madrid, Spain.|Centro Nacional de Biotecnología (CNB-CSIC) - IMDEA Nanociencia Associated Unit , Campus de Cantoblanco, 28049 Madrid, Spain.
authors.forename: Begoña
authors.initials: B
authors.lastname: Sot
authors.affiliation: IMDEA-Nanociencia , Campus de Cantoblanco, 28049 Madrid, Spain.|Centro Nacional de Biotecnología (CNB-CSIC) - IMDEA Nanociencia Associated Unit , Campus de Cantoblanco, 28049 Madrid, Spain.
authors.forename: Alvaro
authors.initials: A
authors.lastname: Somoza
authors.affiliation: IMDEA-Nanociencia , Campus de Cantoblanco, 28049 Madrid, Spain.|Centro Nacional de Biotecnología (CNB-CSIC) - IMDEA Nanociencia Associated Unit , Campus de Cantoblanco, 28049 Madrid, Spain.
authors.forename: Aitziber L
authors.initials: AL
authors.lastname: Cortajarena
mesh_terms: D033942:Adaptor Proteins, Vesicular Transport / Q000096:biosynthesis / Q000737:chemistry* / Q000235:genetics; D000595:Amino Acid Sequence; D001205:Ascorbic Acid / Q000737:chemistry*; D001665:Binding Sites; D015195:Drug Design; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism; D005456:Fluorescent Dyes; D015870:Gene Expression; D006046:Gold / Q000737:chemistry*; D018841:HSP90 Heat-Shock Proteins / Q000138:chemical synthesis / Q000737:chemistry*; D020962:Heterotrimeric GTP-Binding Proteins / Q000096:biosynthesis / Q000737:chemistry* / Q000235:genetics; D008024:Ligands; D053768:Metal Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure; D008969:Molecular Sequence Data; D011485:Protein Binding; D017433:Protein Structure, Secondary; D011994:Recombinant Proteins / Q000096:biosynthesis / Q000737:chemistry / Q000235:genetics; D012710:Serum Albumin, Bovine / Q000737:chemistry; D013050:Spectrometry, Fluorescence
chemical_list: D033942:Adaptor Proteins, Vesicular Transport; D005456:Fluorescent Dyes; D018841:HSP90 Heat-Shock Proteins; D008024:Ligands; D011994:Recombinant Proteins; D012710:Serum Albumin, Bovine; D006046:Gold; D020962:Heterotrimeric GTP-Binding Proteins; D001205:Ascorbic Acid