Ion pairing in water solutions alters both the water hydrogen-bond network and ion solvation, modifying the dynamics and properties of electrolyte water solutions. Here, we report an anomalous intrinsic fluorescence of KCl aqueous solution at room temperature and show that its intensity increases with the salt concentration. From the ab initio density functional theory (DFT) and time-dependent DFT modeling, we propose that the fluorescence emission could originate from the stiffening of the hydrogen bond network in the hydration shell of solvated ion-pairs that suppresses the fast nonradiative decay and allows the slower radiative channel to become a possible decay pathway.
View Article and Find Full Text PDFThe unique properties of liquid water mainly arise from its hydrogen bond network. The geometry and dynamics of this network play a key role in shaping the characteristics of soft matter, from simple solutions to biosystems. Here we report an anomalous intrinsic fluorescence of HCl and NaOH aqueous solutions at room temperature that shows important differences in the excitation and emission bands between the two solutes.
View Article and Find Full Text PDFProtein misfolding and aggregation are associated with a number of human degenerative diseases. In spite of the enormous research efforts to develop effective strategies aimed at interfering with the pathogenic cascades induced by misfolded/aggregated peptides/proteins, the necessary detailed understanding of the molecular bases of amyloid formation and toxicity is still lacking. To this aim, approaches able to provide a global insight in amyloid-mediated physiological alterations are of importance.
View Article and Find Full Text PDFHerein we report the discovery of antimicrobial bridged bicyclic peptides (AMBPs) active against , a highly problematic Gram negative bacterium in the hospital environment. Two of these AMBPs show strong biofilm inhibition and dispersal activity and enhance the activity of polymyxin, currently a last resort antibiotic against which resistance is emerging. To discover our AMBPs we used the concept of chemical space, which is well known in the area of small molecule drug discovery, to define a small number of test compounds for synthesis and experimental evaluation.
View Article and Find Full Text PDFLight chain (AL) amyloidosis, caused by deposition of amyloidogenic immunoglobulin light chains (LCs), is the most common systemic form in industrialized countries. Still open questions, and premises for developing targeted therapies, concern the mechanisms of amyloid formation in vivo and the bases of organ targeting and dysfunction. Investigating amyloid material in its natural environment is crucial to obtain new insights on the molecular features of fibrillar deposits at individual level.
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