FTIR and SAXS study on MBCO-saccharide amorphous systems: protein-matrix reciprocal effects

More than a Confinement: “Soft” and “Hard” Enzyme Entrapment Modulates Biological Catalyst Function

Catalysis makes chemical and biochemical reactions kinetically accessible. From a technological point of view, organic, inorganic, and biochemical catalysis is relevant for several applications, from industrial synthesis to biomedical, material, and food sciences. A heterogeneous catalyst, i.e., a catalyst confined in a different phase with respect to the reagents’ phase, requires either its physical confinement in an immobilization matrix or its physical adsorption on a surface. In this review, we will focus on the immobilization of biological catalysts, i.e., enzymes, by comparing hard and soft immobilization matrices and their effect on the modulation of the catalysts’ function. Indeed, …

BUTENE/H-ZSM-5:STUDIO COMPUTAZIONALE DI MODELLI DI SUPERFICIE E CATALITICI.

Bioprotection Can Be Tuned with Proper Protein/Saccharide Ratio: The Case of Solid Amorphous Matrices

Saccharides, and in particular trehalose, are well known for their high efficiency in protecting biostructures against adverse environmental conditions. The protein dynamics is known to be highly inhibited in a low-water trehalose host medium, the inhibition being markedly dependent on the amount of residual water. Besides hydration, the protein/sugar ratio is expected to affect the properties of saccharide amorphous matrices. In this work, we report an infrared spectroscopy study in dry amorphous matrices of various sugars (the disaccharides trehalose, maltose, sucrose, and lactose, and the trisaccharide raffinose) containing myoglobin, at different protein/sugar ratios. We analyze the str…

Synthesis, characterization and conformational analysis of chloro-bis(glycylglycinate)germanium(IV) chloride

Chloro-bis(glycylglycinate)germanium(IV) chloride, [Cl(glygly)2Ge]Cl, was synthesized and characterized in the solid state by elemental analysis, thermogravimetry and infrared spectroscopy. Solution studies were also performed by 1H-NMR and 13C-NMR in dimethylsulfoxide (DMSO-d6) and by electric conductivity. The structural determination of the complex and the interpretation of the spectroscopic results were performed by employing an integrated computational approach, based on a systematic conformational search analysis on the [Cl(glygly)2Ge]+ ion performed by the Systematic Conformational Search Algorithm (SCSA) code, working at the hybrid B3LYP/6-31G(d,p) level. The combination of experime…

Interconversion among low tier substates in MbCO: an FTIR, Neutron Scattering and Molecular Dynamics simulation study

Information science and computational methods in the modern chemistry education

Internal dynamics and protein-matrix coupling in trehalose-coated proteins.

Abstract We review recent studies on the role played by non-liquid, water-containing matrices on the dynamics and structure of embedded proteins. Two proteins were studied, in water–trehalose matrices: a water-soluble protein (carboxy derivative of horse heart myoglobin) and a membrane protein (reaction centre from Rhodobacter sphaeroides ). Several experimental techniques were used: Mossbauer spectroscopy, elastic neutron scattering, FTIR spectroscopy, CO recombination after flash photolysis in carboxy-myoglobin, kinetic optical absorption spectroscopy following pulsed and continuous photoexcitation in Q B containing or Q B deprived reaction centre from R. sphaeroides . Experimental result…

Structure−Dynamics Coupling between Protein and External Matrix in Sucrose-Coated and in Trehalose-Coated MbCO:  An FTIR Study

We performed FTIR measurements on carboxy-myoglobin (MbCO) embedded in a sucrose−water matrix to study the degrees of freedom coupling between protein and external matrix in such a system. The work was undertaken on the light of recent results by Giuffrida et al. (J. Phys. Chem. B 2003, 107, 13211−13217), who evidenced, in trehalose-coated MbCO, a structured water−sugar environment of the protein, tightly coupled to the heme pocket structure. Such information was obtained through a suitable analysis of the temperature dependence of the CO stretching and of the water association bands in samples of different content of residual water. We applied here the same analysis to sucrose-coated MbCO.…

The Role of Solvent on Protein-Matrix Coupling in MbCO Embedded in Water-Saccharide Systems

Protein Thermal Denaturation and Matrix Glass Transition in Different Protein−Trehalose−Water Systems

Biopreservation by saccharides is a widely studied issue due to its scientific and technological importance; in particular, ternary amorphous protein-saccharide-water systems are extensively exploited to model the characteristics of the in vivo biopreservation process. We present here a differential scanning calorimetry (DSC) study on amorphous trehalose-water systems with embedded different proteins (myoglobin, lysozyme, BSA, hemoglobin), which differ for charge, surface, and volume properties. In our study, the protein/trehalose molar ratio is kept constant at 1/40, while the water/sugar molar ratio is varied between 2 and 300; results are compared with those obtained for binary trehalose…

STRUCTURE-DYNAMICS COUPLING BETWEEN PROTEIN AND EXTERNAL MATRIX IN MBCO EMBEDDED IN VARIOUS SACCHARIDE MATRICES: A FTIR STUDY

BIOPRESERVATION OF MODEL PROTEINS EMBEDDED IN MALTODEXTRINS- AND TREHALOSILDEXTRINS-WATER MATRICES

ROLE OF WATER IN SACCHARIDE BASED BIOPRESERVATION

In this thesis a study, both experimental and computational, on saccharide–based biopreservation is presented, with a particular focus on the role of water in the process. Experiments and simulations have been performed on model systems constituted by a protein (myoglobin) embedded in amorphous solid saccharide–water matrices, which may contain also cosolutes to alter their properties. This study has a dual aim: (a) The understanding of the role of the hydrogen–bond (HB) network present in the saccharide matrix, and its modifications induced by solute content and nature, in the process of biopreservation. Many, among the hypotheses currently discussed to explain the effectiveness of sugars …

Role of residual water hydrogen bonding in sugar/water/biomolecule systems: a possible explanation fortrehalose peculiarity

We report on the set of experimental and simulative evidences which enabled us to suggest how biological structures embedded in a non-liquid water–saccharide solvent are anchored to the surrounding matrix via a hydrogen bond network. Such a network, whose rigidity increases by decreasing the sample water content, couples the degrees of freedom of the biostructure to those of the matrix and gives place to protein–saccharide–water structures (protein–solvent conformational substates). In particular, the whole set of data evidences that, while the protein–sugar interaction is well described in terms of a water entrapment hypothesis, the water replacement hypothesis better describes the sugar–m…

Light-Induced Protein-Matrix Uncoupling and Protein Relaxation in Dry Samples of Trehalose-Coated MbCO at Room Temperature

In humid samples of trehalose-coated carboxy-myoglobin (MbCO), thermally driven conformational relaxation takes place after photodissociation of the carbon monoxide (CO) molecule at room temperature. In such samples, because of the extreme viscosity of the external matrix, photodissociated CO cannot diffuse out of the protein and explores the whole (proximal and distal side) heme pocket, experiencing averaged protein heme pocket structures, as a result of the presence of Brownian motions. At variance, in very dry samples, a lower portion of the photodissociated CO diffuses from the distal to the proximal heme pocket side probing in nonaveraged structures. We revisit here the flash photolysi…

Lipid Phase Transition in Saccharide-Coated Cholate-Containing Liposomes: Coupling to the Surrounding Matrix

The water association band as a marker of hydrogen bonds in trehalose amorphous matrices

The relevant role played by residual water in modulating the dynamics and structure of a protein, a matrix and their coupling has been thoroughly studied in bioprotective amorphous saccharide matrices via experiments and simulations. In order to better characterize this residual water and the hydrogen bond structures in which it is involved, in this work infrared spectroscopy experiments are conducted on trehalose-water systems. The properties of water are inferred from the study of a peculiar infrared band, the water association band, which we exploited as a marker of the hydrogen bonds in which water is involved. Our aim was the identification of populations of water molecules, which give…

Proteins in amorphous saccharide matrices: Structural and dynamical insights on bioprotection

Bioprotection by sugars, and in particular trehalose peculiarity, is a relevant topic due to the implications in several fields. The underlying mechanisms are not yet clearly elucidated, and remain the focus of current investigations. Here we revisit data obtained at our lab on binary sugar/water and ternary protein/sugar/water systems, in wide ranges of water content and temperature, in the light of the current literature. The data here discussed come from complementary techniques (Infrared Spectroscopy, Molecular Dynamics simulations, Small Angle X-ray Scattering and Calorimetry), which provided a consistent description of the bioprotection by sugars from the atomistic to the macroscopic …

A calorimetric study of ternary protein-trehalose-water systems: matrix glass transition and protein thermal denaturation

Protein-solvent coupling in carboxy-myoglobin/sugar/water systems by molecular dynamics simulations

Molecular-Level Characterization of Heterogeneous Catalytic Systems by Algorithmic Time Dependent Monte Carlo

Monte Carlo algorithms and codes, used to study heterogeneous catalytic systems in the frame of the computational section of the NANOCAT project, are presented along with some exemplifying applications and results. In particular, time dependent Monte Carlo methods supported by high level quantum chemical information employed in the field of heterogeneous catalysis are focused. Technical details of the present algorithmic Monte Carlo development as well as possible evolution aimed at a deeper interrelationship of quantum and stochastic methods are discussed, pointing to two different aspects: the thermal-effect involvement and the three-dimensional catalytic matrix simulation. As topical app…

Protein-solvent coupling in carboxy-myoglobin--sugar-water systems by Molecular Dynamics Simulation

Catalytic Supported System Modelled by Computational Approaches

IDEA: interface dynamics and energetics algorithm.

IDEA, interface dynamics and energetics algorithm, was implemented, in FORTRAN, under different operating systems to mimic dynamics and energetics of elementary events involved in interfacial processes. The code included a parallel elaboration scheme in which both the stochastic and the deterministic components, involved in the developed physical model, worked simultaneously. IDEA also embodied an optionally running VISUAL subroutine, showing the dynamic energy changes caused by the surface events, e.g., occurring at the gas-solid interface. Monte Carlo and ordinary differential equation system subroutines were employed in a synergistic way to drive the occurrence of the elementary events a…

Molecular Dynamics simulation of carboxy-myoglobin in trehalose and sucrose-water systems

Light Induced Protein Matrix Decoupling and Protein Relaxation in Dry Samples of Trehalose Coated MbCO at Room Temperature

CO on Nickel: some computational insights about steric hindrance in loaded surfaces

Effect of protein net charge and steric hindrance on the glass transition of Protein-Trehalose-Water systems and on protein thermal denaturation

CO on Ni group metals: a theoretical study

Adsorbed CO on group 10 metal fragments: A DFT study

DFT calculations on the helicopter and cartwheel rotations of one CO molecule adsorbed at the bridge site on metal-surface fragments, characterized by two (M(8)) or three (M(14)) metal-atom layers (M = Ni, Pd, Pt) were performed by the B3LYP[LANL2DZ+6-31 g(d,p)] method, to rationalize the adsorption energetics and the steric hindrance characteristics of surface CO molecules. Potential Energy Surfaces were obtained, either fixing the C-O bond-length or allowing it to change. The behavior of the three metals, as obtained from the study of the configurational space characterizing the CO adsorption on the fragments was explained on the basis of the interaction energies involved in the different…

Coupling between the Thermal Evolution of the Heme Pocket and the External Matrix Structure in Trehalose Coated Carboxymyoglobin

Proteins can assume a very large number of conformations (conformational substates), all concurring to its function. We present experimental evidence for the existence, in trehalose coated carboxymyoglobin, of a structured environment of the protein, tightly coupled to the heme pocket structure, as experienced by the bound CO molecule. This was evidenced by the strict correlation observed between the thermal evolution (300−20 K) of the CO stretching and of the water association bands in samples of carboxymyoglobin embedded in trehalose matrixes of different hydration. This observation put forward the coupling between the degrees of freedom of the matrix and those of the protein. In the drie…

MOLECULAR DYNAMICS SIMULATIONS COMPLEMENT EXPERIMENTAL DATA ON PROTEIN EMBEDDED IN SUGAR-WATER SYSTEMS

SIMPLE MODEL OF GERMANIUM-PEPTIDE INTERACTIONS: BIS-GLYCYLGLYCINE-GERMANIUM-CHLORIDE

Thermal evolution of heme pocket structure in trehalose coated carboxy-myoglobin probed by FTIR measurements

Studi computazionali di proprietà catalitiche di zeoliti acide

Relationship between the Glass Transition of Myoglobin-Water-Disaccharide systems and Protein Thermal Denaturation

Silk-Water: a dynamic duo

Matrix glass transition and embedded protein denaturation: effect of trehalose on different proteins

MbCo in Saccharide Solid Amorphous Systems: A Combined FTIR and SAXS Study

Saccharides, and in particular trehalose, are known for their efficiency in protecting biostructures against environmental stress [1], although the preservation mechanism is still debated. Experiments and simulations [2,3] on carboxy-myoglobin (MbCO) showed that the protein dynamics is highly inhibited in dry trehalose matrices, the inhibition being dependent on the water content. In these conditions, a mutual protein-matrix structural and dynamic influence is observed.Here we report a combined FTIR and SAXS study on MbCO embedded in dry amorphous matrices of trehalose and sucrose. FTIR measurements were performed at different protein/sugar ratios, focussing on the stretching band of the bo…

Water effects on trehalose matrices studied through Molecular Dynamics

Myoglobin embedded in saccharide amorphous matrices: water-dependent domains evidenced by small angle X-ray scattering

We report Small Angle X-ray Scattering (SAXS) measurements performed on samples of carboxy-myoglobin (MbCO) embedded in low-water trehalose glasses. Results showed that, in such samples, "low-protein" trehalose-water domains are present, surrounded by a protein-trehalose-water background; such finding is supported by Infrared Spectroscopy (FTIR) measurements. These domains, which do not appear in the absence of the protein and in analogous sucrose systems, preferentially incorporate the incoming water at the onset of rehydration, and disappear following large hydration. This observation suggests that, in organisms under anhydrobiosis, analogous domains could play a buffering role against th…

MbCO↔matrix reciprocal effects in low hydration amorphous saccharide systems: a FTIR study

Role of Solvent on Protein-Matrix Coupling in MbCO Embedded in Water-Saccharide Systems: A Fourier Transform Infrared Spectroscopy Study

AbstractEmbedding protein in sugar systems of low water content enables one to investigate the protein dynamic-structure function in matrixes whose rigidity is modulated by varying the content of residual water. Accordingly, studying the dynamics and structure thermal evolution of a protein in sugar systems of different hydration constitutes a tool for disentangling solvent rigidity from temperature effects. Furthermore, studies performed using different sugars may give information on how the detailed composition of the surrounding solvent affects the internal protein dynamics and structural evolution. In this work, we compare Fourier transform infrared spectroscopy measurements (300–20K) o…

Molecular Dynamics simulation of carboxy-myoglobin in trehalose and sucrose-water systems

“Water Association” Band in Saccharide Amorphous Matrices: Role of Residual Water on Bioprotection

Saccharides protect biostructures against adverse environmental conditions mainly by preventing large scale motions leading to unfolding. The efficiency of this molecular mechanism, which is higher in trehalose with respect to other sugars, strongly depends on hydration and sugar/protein ratio. Here we report an Infrared Spectroscopy study on dry amorphous matrices of the disaccharides trehalose, maltose, sucrose and lactose, and the trisaccharide raffinose. Samples with and without embedded protein (Myoglobin) are investigated at different sugar/protein ratios, and compared. To inspect matrix properties we analyse the Water Association Band (WAB), and carefully decompose it into sub-bands,…

Water association band : anuseful tool for studying the water structure in samples of low water content

CONFORMATIONAL ANALYSIS AND DFT-GIAO 13CNMR CHEMICAL SHIFT CALCULATION OF DIMETHYLTIN(IV)-D-RIBONATE COMPLEX

Protein-solvent coupling in myoglobin-sugar-water systems: a Molecular Dynamics study

Water Association Band as marker of the matrix structure in amorphous saccharide and saccharide–protein samples

Quantum chemical models of acidic sites in H-ZSM-5 zeolites

Thermal Behavior of dry and hydrated MbCO crowded systems

Protein-Matrix Coupling in MbCO embedded in saccharide matrices

Closed-Locked and Apo-Resting State Structures of the Human α7 Nicotinic Receptor: A Computational Study

International audience; Nicotinic acetylcholine receptors, belonging to the Cys-loop super-family of ligand-gated ion channels (LGICs), are membrane proteins present in neurons and at neuromuscular junctions. They are responsible for signal transmission, and their function is regulated by neurotransmitters, agonists and antagonists drugs. A detailed knowledge of their conformational transition in response to ligand binding is critical to understand the basis of ligand-receptor interaction, in view of new pharmacological approaches to control receptor activity. However, the scarcity of experimentally derived structures of human channels makes this perspective extremely challenging. To contri…

Biopreservation of model proteins embedded in maltodextrins- and trehalosildextrins–water matrices

Structural and Kinetic DFT Characterization of Materials to Rationalize Catalytic Performance

This review shortly discusses recent results obtained by the application of density functional theory for the calculations of the adsorption and diffusion properties of small molecules and their reactivity on heterogenous catalytic systems, in the ambit of the Nanocat project. Particular focus has been devoted to palladium catalysts, either in atomic or small cluster form. Some protocols have been tested to obtain efficient ways able to treat the electronic and geometric influence of supports like zeolites and carbon nanotubes on the catalytic properties of palladium. The hydroisomerization of cis-but-2-ene is discussed as model reaction on supported and unsupported Pd clusters. Some prelim…

Protein-solvent coupling in carboxymyoglobin/sugar/water systems by molecular dynamics simulation

Computational Aspects in heterogeneous nano-catalysis

A concise description of the metods,which we have developed and employed in studying, by first principle computational models, the field of the heterogeneous catalysis is reported here along with obtained results. In this frame, the main characterstics of the time dependent Monte Carlo modelling are illustrated. The importance of using Monte Carlo models supported by high level quantum-mechanical information, to find alternative lines in studying heterogeous catalysis and designing new catalytic experiments and applications at nanoscopic level, is stressed. Technical details are illustrated, considering applications for the hydrogenation of organic substrates on metal catalysts in two-and t…

Protein-solvent coupling in carboxy-myoglobin-sugar-water systems Molecular Dynamics Simulations and Experiments

Catalysis in confined spaces: computational study of H-ZSM5 zeolite reactivity

DFT study of but-2-ene isomerization on H-ZSM-5 modified catalyst

H−ZSM-5 Modified Zeolite:  Quantum Chemical Models of Acidic Sites

A ZSM-5 fragment, containing 52 tetrahedral moieties, each of them formed by one silicon or one aluminum atom surrounded by four oxygen atoms, was employed to model (52T systems) by quantum chemical calculations (i) the influence of the positions of the acidic sites on the energetics of 22 aluminum monosubstituted and bisubstituted 52T acidic zeolite (H-ZSM-5) systems and (ii) the local adsorption properties and acidic strength of the corresponding -OH sites. The energetics and the structural properties of simpler acid H-ZSM-5 systems containing only five Tetrahedral moieties (5T systems) were also modeled for comparison. B3LYP/6-31G(d,p) partial geometry optimization routines were performe…

Structure and Dynamics in Glassy and Plasticized Amorphous Disaccharide-Water Samples: A FTIR Study

Biopreservation of Myoglobin in Crowded Environment: A Comparison between Gelatin and Trehalose Matrixes.

Biopreservation by sugar and/or polymeric matrixes is a thoroughly studied research topic with wide technological relevance. Ternary amorphous systems containing both saccharides and proteins are extensively exploited to model the in vivo biopreservation process. With the aim of disentangling the effect of saccharides and polypeptidic crowders (such as gelatin) on the preservation of a model protein, we present here a combined differential scanning calorimetry and UV-vis spectrophotometry study on samples of myoglobin embedded in amorphous gelatin and trehalose + gelatin matrixes at different hydrations, and compare them with amorphous myoglobin-only and myoglobin-Trehalose samples. The res…

Thermal denaturation of myoglobin in water--disaccharide matrixes: relation with the glass transition of the system.

Proteins embedded in glassy saccharide systems are protected against adverse environmental conditions [Crowe et al. Annu. Rev. Physiol. 1998, 60, 73-103]. To further characterize this process, we studied the relationship between the glass transition temperature of the protein-containing saccharide system (T(g)) and the temperature of thermal denaturation of the embedded protein (T(den)). To this end, we studied by differential scanning calorimetry the thermal denaturation of ferric myoglobin in water/disaccharide mixtures containing nonreducing (trehalose, sucrose) or reducing (maltose, lactose) disaccharides. All the samples studied are, at room temperature, liquid systems whose viscosity …

Thermal evolution of the CO stretching band in carboxy-myoglobin in the light of neutron scattering and molecular dynamics simulations

Abstract As it is well known, the thermal behaviour of the CO stretching band in MbCO reflects the interconversion among protein’s taxonomic and lower tier substates. We compare here FTIR data on the thermal behaviour of the CO stretching band in MbCO embedded in non-liquid, water–trehalose matrixes, and neutron scattering data on dry and hydrated proteins and nucleic acids. The comparison, also in the light of simulative data, gives relevant information on the relationship between the mean square displacements of hydrogen atoms and the heme pocket thermal rearrangements in MbCO, as experienced by the bound CO, in the temperature region 100–200 K, and at higher temperature when large scale …

SAXS Study on Myoglobin Embedded in Amorphous Saccharide Matrices

We report on Small Angle X-ray Scattering (SAXS) measurements performed on samples of carboxy-myoglobin and met-myoglobin embedded in low hydrated matrices of four different saccharides (trehalose, sucrose, maltose and lactose). Results confirm the already reported occurrence of inhomogeneities, which are not peculiar of trehalose samples, but appear also in maltose and lactose, and in some cases also sucrose, being dependent on the sample hydration and on the presence of sodium dithionite. This behaviour confirms our previous interpretation about the nature of the inhomogeneities, and prompt it as a possible general behaviour for highly concentrated sugar matrices.

SAXS and FTIR study on MbCO-Saccharide amorphous systems

Modeling of catalytic materials: advances in studying different supports

A FTIR study on low hydration saccharide amorphous matrices: Thermal behaviour of the Water Association Band

Abstract We report a study on the thermal behaviour of the infrared Water Association Band (WAB) in dry binary saccharide–water systems (containing trehalose, sucrose, maltose, and raffinose). This is a follow-up of preceding studies on analogous carboxymyoglobin-saccharide–water ternary systems, which pointed out a mutual protein-matrix influence (coupling). A comparison between binary and ternary systems, for all the saccharides studied, evidences a reduction in the residual water content in the latter and, except for trehalose, a sizable modification in the thermal behaviour, which is discussed in terms of structure and hydrogen bonding properties of the sugars. The study allowed us also…

Thermal Denaturation of Myoglobin in Water–Sugar Matrices and Relationship with the Glass Transition of the System

Molecular dynamics simulation of sucrose- and trehalose-coated carboxy-myoglobin

We performed a room temperature molecular dynamics (MD) simulation on a system containing 1 carboxy-myoglobin (MbCO) molecule in a sucrose–water matrix of identical composition (89% [sucrose/(sucrose + water)] w/w) as for a previous trehalose–water–MbCO simulation (Cottone et al., Biophys J 2001;80:931–938). Results show that, as for trehalose, the amplitude of protein atomic mean-square fluctuations, on the nanosecond timescale, is reduced with respect to aqueous solutions also in sucrose. A detailed comparison as a function of residue number evidences mobility differences along the protein backbone, which can be related to a different efficacy in bioprotection. Different heme pocket struc…

FTIR Study on Reciprocal Protein↔Matrix effects in dry amorphous saccharide systems

Role of Solvent on Protein-Matrix Coupling in MbCO Embedded in Water-Saccharide Systems: an FTIR study.

Embedding protein in sugar systems of low water content enables one to investigate the protein dynamicstructure function in matrixes whose rigidity is modulated by varying the content of residual water. Accordingly, studying the dynamics and structure thermal evolution of a protein in sugar systems of different hydration constitutes a tool for disentangling solvent rigidity from temperature effects. Furthermore, studies performed using different sugars may give information on how the detailed composition of the surrounding solvent affects the internal protein dynamics and structural evolution. In this work, we compare Fourier transform infrared spectroscopy measurements (300–20 K) on MbCO e…

Curriculum didattico del Chimico Moderno: Discipline Informatiche e Computazionali

Water association band as a marker of the matrix structure in amorphous saccharide and saccharide-protein samples

Metodi quantomeccanici e Monte Carlo applicati a sistemi nanostrutturati

MbCO embedded in trehalosyldextrin matrices: thermal effects and protein-matrix coupling

Saccharide-based biopreservation is widely studied because of its scientific importance and possible technological outcomes for food and pharmaceutical industries. Ternary protein/saccharide/water systems have been extensively exploited to model the characteristics of the in vivo biopreservation process. A tight, water dependent, protein–matrix coupling has been shown to occur in various simple saccharide amorphous matrices, which is stronger in trehalose. The efficiency as bioprotectant of trehalose has been ascribed to this tight coupling, since the appearance of damages on biological structures will more involve structural variations of the surrounding matrix. Here we present, as an appl…