Spectroscopic Studies of Buffer and Metal Ion Effects on Amyloid-Beta Peptide Structure and Aggregation

Abstract

Amyloid-β peptides are found in brains obtained from Alzheimer's patients. These peptides aggregate forming insoluble Amyloid-β plaques. It is uncertain how the presence of these peptide plaques correlate with the onset of the disease, however environmental conditions are known to alter disease progression. Previous studies have proven that metal ions such as zinc and copper are co-localized within Aβ plaques. Recent studies suggest that these metal ions may serve a role in inducing Aβ peptide misfolding and aggregation. The Cu2+ and Zn2+ ions are believed to bind to the Aβ peptide structure and increase aggregation. The metal ion concentrations play a factor as higher metal ion concentrations correlate with a higher aggregation rate. Understanding the environmental conditions that affect Aβ peptide structure and aggregation will provide a greater understanding about the role of metals in disease. Current studies are aimed at understanding how metal ions influence peptide structure, solvation, and aggregation. Infrared spectroscopy was used to monitor aggregation and structural changes of control Aβ peptide and Aβ peptide in the presence of Cu2+ and Zn2+ over time. Infrared spectra show that peptide length, buffer and metal concentration influence Aβ peptide structure, solvation, and aggregation. AcknowledgementsNSF-REU #1461175JMU Department of Chemistry and Biochemistry