Misfolding of proteins leads to insoluble protein deposits, which eventually causes neurodegenerative diseases such as Alzhiemers and Parkinsons. We are investigating the molecular basis of peptide aggregation and protein deposition. The transformation process from �-helices to �-sheet structures appear to play a major role in the fibril formation and aggregation of such peptides. In addition, their binding properties with metals and other proteins are considered to play a significant role, in particular because there is an abundance of certain metal ions in brain tissue. In lieu of this, we have studied the binding properties of �-amyloid and �-synuclein peptides with several metal ions including Pd, Ni, Cu, Zn, Mg, Al and Cd ions. The studies may further shed light on the metallochemistry associated with Alzhiemer's disease and the impact of secondary structure transformation at the molecular level. In addition to metal ions, in order to further decipher the mechanism of aggregation, we have also examined their interactions with synthetic peptide nanovesicles and nanotubes as a function of pH, and solvent polarity.

The interactions of the aggregating systems were studied using atomic force microscopy, circular dichroism, transmission electron microscopy, zeta potential measurements, dynamic light scattering and infrared spectroscopy. Our studies reveal that at certain pH, the �-synuclein can bind to the nanovesicles leading to a reduction in fibril formation. Similar studies are ongoing with the beta-amyloid peptides as well.