Emanuela Gatto - Academia.edu (original) (raw)

Papers by Emanuela Gatto

An entry from the Cambridge Structural Database, the world's repository for small molecule cr... more An entry from the Cambridge Structural Database, the world's repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

International Journal of Biological Macromolecules, 2020

This is a PDF file of an article that has undergone enhancements after acceptance, such as the ad... more This is a PDF file of an article that has undergone enhancements after acceptance, such as the addition of a cover page and metadata, and formatting for readability, but it is not yet the definitive version of record. This version will undergo additional copyediting, typesetting and review before it is published in its final form, but we are providing this version to give early visibility of the article. Please note that, during the production process, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.

Energies

In September 2015, the ONU approved the Global Agenda for Sustainable Development, by which all c... more In September 2015, the ONU approved the Global Agenda for Sustainable Development, by which all countries of the world are mobilized to adopt a set of goals to be achieved by 2030. Within these goals, the aim of having a responsible production and consumption, as well as taking climate action, made is necessary to design new eco-friendly materials. Another important UN goal is the possibility for all the countries in the world to access affordable energy. The most promising and renewable energy source is solar energy. Current solar cells use non-biodegradable substrates, which generally contribute to environmental pollution at the end of their life cycles. Therefore, the production of green and biodegradable electronic devices is a great challenge, prompted by the need to find sustainable alternatives to the current materials, particularly in the field of dye-sensitized solar cells. Within the green alternatives, biopolymers extracted from biomass, such as polysaccharides and protei...

Nanomaterials, 2022

Self-assembly is the most suitable approach to obtaining peptide-based materials on the nano- and... more Self-assembly is the most suitable approach to obtaining peptide-based materials on the nano- and mesoscopic scales. Applications span from peptide drugs for personalized therapy to light harvesting and electron conductive media for solar energy production and bioelectronics, respectively. In this study, we will discuss the self-assembly of selected model and bioactive peptides, in particular reviewing our recent work on the formation of peptide architectures of nano- and mesoscopic size in solution and on solid substrates. The hierarchical and cooperative characters of peptide self-assembly will be highlighted, focusing on the structural and dynamical properties of the peptide building blocks and on the nature of the intermolecular interactions driving the aggregation phenomena in a given environment. These results will pave the way for the understanding of the still-debated mechanism of action of an antimicrobial peptide (trichogin GA IV) and the pharmacokinetic properties of a pe...

Journal of Peptide Science

Synthetic therapeutic peptides (STP) are intensively studied as new-generation drugs, characteriz... more Synthetic therapeutic peptides (STP) are intensively studied as new-generation drugs, characterized by high purity, biocompatibility, selectivity and stereochemical control. However, most of the studies are focussed on the bioactivity of STP without considering how the formulation actually used for therapy administration could alter the physico-chemical properties of the active principle. The aggregation properties of a 20-mer STP (Ac-His-Ala-Arg-Ile-Lys-D-Pro-Thr-Phe-Arg-Arg-D-Leu-Lys-Trp-Lys-Tyr-Lys-Gly-Lys-Phe-Trp-NH2 ), showing antitumor activity, were investigated by optical spectroscopy and atomic force microscopy imaging, as itself (CIGB552) and in its therapeutic formulation (CIGB552TF). It has found that the therapeutic formulation deeply affects the aggregation properties of the investigated peptide and the morphology of the aggregates formed on mica by deposition of CIGB552 and CIGB552TF millimolar solutions. Molecular dynamics simulations studied the first steps of CIGB552 aggregation under physiological ionic strength conditions (NaCl 150 mM), showing that peptide oligomers, from dimers to tetramers, are preferentially formed in this environment. Interestingly, cell viability assays performed on H-460 cell lines indicate a major antiproliferative activity of the peptide in its therapeutic formulation with respect to the peptide aqueous solution.

... Autori: Caruso, M; Bocchinfuso, G; Palleschi, A; Gatto, E; Formaggio, F; Toniolo, C; Venanzi,... more ... Autori: Caruso, M; Bocchinfuso, G; Palleschi, A; Gatto, E; Formaggio, F; Toniolo, C; Venanzi, M. ... Lingua: eng. Tipologia: Intervento a convegno. Citazione: Caruso, M., Bocchinfuso, G., Palleschi, A., Gatto, E., Formaggio, F., Toniolo, C., et al. (2010). ...

Chemistry – A European Journal

External stimuli are potent tools that Nature uses to control protein function and activity. For ... more External stimuli are potent tools that Nature uses to control protein function and activity. For instance, during viral entry and exit, pH variations are known to trigger large protein conformational changes. In Nature, also the electron transfer (ET) properties of ET proteins are influenced by pH-induced conformational changes. In this work, a pH-controlled, reversible 3 10 -helix to α-helix conversion (from acidic to highly basic pH values and vice versa ) of a peptide supramolecular system built on a gold surface is described. The effect of pH on the ability of the peptide SAM to generate a photocurrent was investigated, with particular focus on the effect of the pH-induced conformational change on photocurrent efficiency. The films were characterized by electrochemical and spectroscopic techniques, and were found to be very stable over time, also in contact with a solution. They were also able to generate current under illumination, with an efficiency that is the highest recorded so far with biomolecular systems.

The Journal of Physical Chemistry B

Peptide self-assembly is ubiquitous in nature. It governs the organization of proteins, controlli... more Peptide self-assembly is ubiquitous in nature. It governs the organization of proteins, controlling their folding kinetics and preserving their structural stability and bioactivity. In this connection, model oligopeptides may give important insights into the molecular mechanisms and elementary forces driving the formation of supramolecular structures. In this contribution, we show that a single residue substitution, that is, Aib (α-aminoisobutyric acid) in place of Ala at position 4 of an -(l-Ala)5-homo-oligomer, strongly alters the aggregation process. In particular, this process is initiated by the formation of small peptide clusters that promote aggregation on the nanometer scale and, through a hierarchical self-assembly, lead to mesoscopic structures of micrometric dimensions. Furthermore, we show that the use of the well-established Langmuir-Blodgett technique represents an effective strategy for coating extended areas of inorganic substrates by densely packed peptide layers, thus paving the way for application of peptide films as templates for biomineralization, biocompatible coating of surfaces, and scaffolds for tissue engineering.

ChemistrySelect

We investigated the effect of gold nanoparticles (AuNPs) on the aggregation of a CFF (C = cystein... more We investigated the effect of gold nanoparticles (AuNPs) on the aggregation of a CFF (C = cysteine; F = phenylalanine) tripeptide (derived from Aβ peptide) in aqueous medium. Special attention was dedicated to the role of AuNPs as inducers and inhibitors during nucleation kinetics and the structure of the resulting scaffolds was carefully investigated. At millimolar concentrations, the tripeptide was found to form β-sheet structures organized into long filaments. Spectral signatures and topography of the filaments were studied by Raman spectroscopy and atomic force microscopy (AFM), revealing that conjugation to AuNPs not only stabilizes the system, but also inhibit or enhance amyloid-like features depending on the synthesis route used in the preparation of AuNPs. Sodium borohydride (NaBH4) mediated synthesis of AuNPs gave rise to a strong absorption peak close to 520 nm, indicating that AuNPs were dispersed, independently of the peptide concentration added in the reaction. However, when the peptide/gold salt mixture was heated at 60°C, AuNPs and AuNP-decorated filaments were both formed in solution and the fractions of which population were found to be dependent on the [HAuCl4]/[CFF] ratio, as illustrated by TEM images. In addition, the insertion of AuNPs at the surface of CFF nanostructures can promote electron transfer from the metallic nanoparticles to the CFF surface, creating an n-type semiconductor, and causing a peak shift of the phenylalanine absorption band.

Angewandte Chemie

A work of chemical engineering has been realized on gold surfaces. Three building blocks have bee... more A work of chemical engineering has been realized on gold surfaces. Three building blocks have been designed, in order to chemically link the surface and vertically self assemble in an ordered manner in 3D, through thymine-adenine hydrogen bonds. Starting from these building blocks, we have engineered two different films on gold surface. In film 1, two components are used: adenine linked to a lipoic acid molecule (Lipo-A) to covalently bind the gold surface, and ZnTPP linked to a thymine molecule (T-ZnTPP). Film 2 has an additional noncovalently linked layer: a helical undecapeptide analogue of the Thricogin GA IV peptide, in which four glycine were replaced by four lysine residues to favor helical conformation and reduce conformational flexibility, and in which the two extremities were functionalized with thymine and adenine, for binding of, respectively, Lipo-A and T-ZnTPP. These films have been characterized by electrochemical and spectroscopic techniques, and have been found to be very stable over time, also in contact with a solution. They were also able to generate current under illumination, with an efficiency higher than the one recorded in similar systems. The three-dimensional (3D) organization of molecules on surfaces remains an ongoing challenge in the field of materials science. 1 In particular, the molecular order and perfect positioning of

Peptide Science

Trichogin GA IV (TrGA) is an antimicrobial peptide isolated from Trichoderma longibrachiatum. The... more Trichogin GA IV (TrGA) is an antimicrobial peptide isolated from Trichoderma longibrachiatum. The amino acid sequence of TrGA is rather peculiar, because it is characterized by three Aib and four Gly residues, which confer unique dynamic and structural properties. In a previous study, we found that TrGA shows excellent binding properties to Ca(II) and lanthanide Gd(III) ions in acetonitrile solutions. Within the lanthanide ions, Tb(III) ions possess fascinating optical characteristics, such as luminescence which greatly improves after coordination. Here, we present the results of our spectroscopic and molecular dynamics investigations on the Tb(III) ion-binding properties of an N -Fmoc functionalized analog of Trichogin GA IV (F0TrOMe). The high Tb(III) ion-F0TrOMe affinity, together with the proteolytic resistance and membrane affinity of the natural compound, confers to this system potentially promising applications in several fields, such as bioimaging and bioanalytical assays.

J. Mater. Chem. C

KuQuinones deposited on ITO surface by Langmuir–Blodgett technique acted as photosensitizers, giv... more KuQuinones deposited on ITO surface by Langmuir–Blodgett technique acted as photosensitizers, giving interesting results due to their pentacyclic, highly conjugated structure, and a very low reduction potential.

Journal of Photochemistry and Photobiology A: Chemistry

A dodecapeptide (AMRKLPDAPGMH) functionalized with a tetramethylrhodamine (TAMRA) chromophore at ... more A dodecapeptide (AMRKLPDAPGMH) functionalized with a tetramethylrhodamine (TAMRA) chromophore at the N-terminus was immobilized on nanocrystalline TiO 2. The optical and binding properties of the peptide layer immobilized on the titania surface were characterized by UV-vis absorption, steadystate fluorescence and X-ray photoelectron spectroscopies. Circular Dichroism experiments and Molecular Mechanics calculations showed that the predominant conformation populated by the peptide scaffold brings Arg3, Lys4 and Asp7 in the correct position for linking the TiO 2 surface. Photocurrent generation experiments were therefore carried out to determine the photon-to-current conversion efficiency (IPCE) of a Grätzel-like Dye Sensitized Solar Cell (DSSC), the photoactive unit of which is formed by TAMRA-AMRKLPDAPGMH/TiO 2. The measured IPCE amounted to 0.65%, a value that is definitely low, but superior to those previously reported for similar bioinspired DSSCs. This result can be ascribed to the light-harvesting properties of the TAMRA chromophore and to the unique structural properties of the peptide spacer.

Journal of Peptide Science, 2017

The role of the conformationally constrained α-aminoisobutyric acid (Aib) residue in the aggregat... more The role of the conformationally constrained α-aminoisobutyric acid (Aib) residue in the aggregation and self-assembly properties of oligopeptides is discussed, critically reviewing our recent work in the field. In this connection, three significant case studies are presented: (i) aggregation propensity of Aib homo-oligopeptides of different length; (ii) perturbation of the conformational and aggregation properties of Ala-based pentapeptides by a single Aib versus Ala substitution; and (iii) build up of self-assembled monolayers formed by Aib homo-hexapeptide building blocks. The peptides investigated were all functionalized by a fluorescent probe, that is, a naphthyl group in the first case-study and a pyrenyl group in the other two, with the aim at applying optical spectroscopy techniques and evaluating the relevance of aromatic interactions in the aggregation process. Microscopy techniques at nanometric resolution and results of molecular dynamics simulations are also presented to analyze how the conformational properties of the peptide building blocks would affect the morphology of the peptide aggregates from the nanoscale to the mesoscale. Copyright © 2017 European Peptide Society and John Wiley &amp;amp; Sons, Ltd.

Zeitschrift für Physikalische Chemie, 2016

Multidentate binding of two helical hexapeptides to a gold surface was obtained by introducing in... more Multidentate binding of two helical hexapeptides to a gold surface was obtained by introducing in the peptide chain a non ribosomial amino acid, i.e. the 4-amino-1,2-dithiolane-4-carboxylic acid (Adt) residue, a C

Dalton Trans., 2016

Tetraferrocenylporphyrins have been successfully deposited on ITO electrodes for O2 photo-catalyt... more Tetraferrocenylporphyrins have been successfully deposited on ITO electrodes for O2 photo-catalytic activation.