Innovative results in the Biostructure Section have been achieved during
the year 2002 in the structural study of the ribosome, the complex
machinery which is responsible for protein biosynthesis in cells. The
determination of the ribosome structure allows gathering of information on
its mechanisms of action and inhibition. In this framework, researchers of
the Institute of Biostructure and Bioimaging, in collaboration with Max
Planck Institut (Hamburg, Germany) and Weizmann Institute (Rehovot,
Israel), have gained novel information on the ribosome action mechanism by
studying the x-ray structures of complexes between the ribosome and
substrate analogues. In addition, x-ray structures of complexes with
antibiotics have provided structural bases for inactivating mechanisms by
these drugs.
Innovative results in the Bioimaging Section and in the Catania Section
have been achieved in the neurodegenerative disorders. Early diagnostic
characterization and follow up with emission tomographic techniques are
important goals of ongoing research programs. Our Bioimaging Section is
currently investigating the predictive value of specific patterns of
cerebral blood flow changes and benzodiazepine GABAA receptor
abnormalities in the development of Alzheimer's disease in patients with
mild memory impairment. Preliminary results show the following pattern:
decreased blood flow in the posterior cyngulus and in the parietal cortex,
and loss of benzodiazepine receptors in the parahippocampal region. We are
also evaluating the dopamine transporter to assess the involvement of the
nigro-striatal system in early onset Parkinson's disease with and without
mutation in the parkin gene. In the first group of patients a 60-70%
decrease in DAT density more severe and symmetric in patients with parkin+
was found. These research programs may offer new insights in the
pathogenesis, characterization and therapeutic approach in selected
neurodegenerative disorders.
In the Catania Section the research activity has been mainly focused on
the study of synthetic peptides from the Prion Protein's domain. In
particular, the interactions of such peptides with copper (II) as well as
artificial membranes have been studied by using a spectroscopic and
thermodynamic approach. Useful data on the role played by the metal ion to
promote conformational transition toward beta-sheet rich aggregate forms,
and the distinct tendency showed by these peptides fragments to interact
with artificial lipid membranes have been obtained. In addition to the
above reported studies, valuable results have been achieved concerning the
synthesis of beta-cyclodextrin derivatives showing antioxidant properties
or designed for the site specific delivery and release of pharmaceutically
active compounds.
Focus