Secondary structural modifications of A beta(1-40) induced by multiple 2-acetoxy-4-methoxybenzyl (acetylHmb) protection

Abstract

Modifications to secondary structure and fibril formation caused by multiple acetylHmb backbone amide protection of Alzheimer's disease Aβ(1-40) were investigated using circular dichroism spectroscopy and electron microscopy. Penta(acetylHmb)Aβ(1-40) was observed to have a reduced ability to form α-helix and β-sheet structures under the same solution conditions as the native peptide, with α-helical propensity being reduced more significantly than β-sheet propensity. Further, acetylHmb backbone protection was found to alter Aβ(1-40) interaction with SDS-micelles by preventing α-helix formation. Aβ fibril formation, a characteristic property of this peptide, was also not observed for penta(ace..