title: Interaction of Thermus thermophilus ArsC enzyme and gold nanoparticles naked-eye assays speciation between As(III) and As(V).
abstract: The thermophilic bacterium Thermus thermophilus HB27 encodes chromosomal arsenate reductase (TtArsC), the enzyme responsible for resistance to the harmful effects of arsenic. We report on adsorption of TtArsC onto gold nanoparticles for naked-eye monitoring of biomolecular interaction between the enzyme and arsenic species. Synthesis of hybrid biological-metallic nanoparticles has been characterized by transmission electron microscopy (TEM), ultraviolet-visible (UV-vis), dynamic light scattering (DLS) and phase modulated infrared reflection absorption (PM-IRRAS) spectroscopies. Molecular interactions have been monitored by UV-vis and Fourier transform-surface plasmon resonance (FT-SPR). Due to the nanoparticles' aggregation on exposure to metal salts, pentavalent and trivalent arsenic solutions can be clearly distinguished by naked-eye assay, even at 85 μM concentration. Moreover, the assay shows partial selectivity against other heavy metals.
authors.affiliation: Institute for Microelectronics and Microsystems, Unit of Naples-National Research Council Via P. Castellino 111, 80127, Italy.|Department of Chemical Sciences, University of Naples 'Federico II', Via Cynthia, 80126 Naples Italy.
authors.forename: Jane
authors.initials: J
authors.lastname: Politi
authors.affiliation: Sorbonne Universités, UPMC Univ Paris VI, Laboratoire de Réactivité de Surface, 4 place Jussieu, F-75005 Paris, France.|CNRS, UMR 7244, CSPBAT, Laboratoire de Chimie, Structures et Propriétés de Biomateriaux et d'Agents Therapeutiques Université Paris 13, Sorbonne Paris Cité, Bobigny, France CNRS, Paris, France.
authors.forename: Jolanda
authors.initials: J
authors.lastname: Spadavecchia
authors.affiliation: Department of Biology, University of Naples 'Federico II', Via Cynthia, 80126 Naples, Italy.
authors.forename: Gabriella
authors.initials: G
authors.lastname: Fiorentino
authors.affiliation: Department of Biology, University of Naples 'Federico II', Via Cynthia, 80126 Naples, Italy.
authors.forename: Immacolata
authors.initials: I
authors.lastname: Antonucci
authors.affiliation: Sorbonne Universités, UPMC Univ Paris VI, Laboratoire de Réactivité de Surface, 4 place Jussieu, F-75005 Paris, France.
authors.forename: Sandra
authors.initials: S
authors.lastname: Casale
authors.affiliation: Institute for Microelectronics and Microsystems, Unit of Naples-National Research Council Via P. Castellino 111, 80127, Italy.
authors.forename: Luca
authors.initials: L
authors.lastname: De Stefano
mesh_terms: D053502:Arsenate Reductases / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D001151:Arsenic / Q000737:chemistry*; D001426:Bacterial Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D006046:Gold / Q000737:chemistry*; D007477:Ions / Q000737:chemistry; D053768:Metal Nanoparticles / Q000737:chemistry*; D046529:Microscopy, Electron, Transmission; D010316:Particle Size; D011092:Polyethylene Glycols / Q000737:chemistry; D011994:Recombinant Proteins / Q000096:biosynthesis / Q000737:chemistry / Q000302:isolation & purification; D013056:Spectrophotometry, Ultraviolet; D017550:Spectroscopy, Fourier Transform Infrared; D020349:Surface Plasmon Resonance; D016963:Thermus thermophilus / Q000201:enzymology*
chemical_list: D001426:Bacterial Proteins; D007477:Ions; D011994:Recombinant Proteins; D011092:Polyethylene Glycols; D006046:Gold; D053502:Arsenate Reductases; D001151:Arsenic