Research themes
Use of bioenergetically active membranes for the study of eco-compatible solvents
The use of eco-compatible substances is the primary objective of green chemistry. Among these, eco-compatible solvents and surfactants (ionic liquids, eutectic solvents) and biobased chemicals have a central role. The interaction of these compounds with biological entities and their environmental impact vary considerably and show a high species-specificity. In our laboratory, the effects of substances considered green on the integrity of native biological membranes isolated from photosynthetic bacteria and their effects on the growth of microorganisms in culture are studied. The use of bioenergetically active biological membranes, isolated in vesicular form, offers the advantage of deepening the mechanism of action of exogenous molecules, allowing to distinguish between direct inhibition on one or more of the complexes responsible for energy transduction and indirect inhibition, due to the decoupling of the proton-motive force from the synthesis of ATP.
Bioprotection mechanisms in dehydrated glass matrices
The insertion of biomolecules proteins into sufficiently dehydrated glassy matrices of the disaccharides trehalose and sucrose produces a drastic inhibition of the conformational dynamics of the biomolecule on a large time scale, determining its exceptional thermal stability. This behavior is the basis of the natural phenomenon of anhydrobiosis and numerous applications in the pharmaceutical and biotechnological fields. Our group, in collaboration with L. Cordone (Department of Physics and Astronomy, University of Palermo), has formulated a molecular model of bioprotection (anchorage hypothesis) which traces dynamic protein-matrix coupling to the formation of extended H-bond networks to surface groups of the protein, residual water molecules and disaccharide. To verify the model and define its molecular details, we characterize the structure and dynamics of amorphous matrices formed by model proteins and disaccharides (or other cosolutes synthesized under stress conditions by anhydrobiotic organisms) using static FTIR spectroscopy. Recently these studies have been extended to the characterization of the bioprotective properties of dehydrated matrices consisting of intrinsically disordered proteins (CAHS), purified from anhydrobiotic organisms.