Thursday 24. January 2019
Jana Wägele on “Influence of fluorescent tags on Aβ1-40 oligomerization”
Zhanna Evgrafova on “Modulation of Amyloid b Peptide Aggregation by Hydrophilic Polymers”
Von-Danckelmann-Platz 3, SR 1.06
06120 Halle (Saale)
Time: 3.30pm - 5.00pm
Link to OpenStreetMap
Influence of fluorescent tags on Aβ1-40 oligomerization
Low molecular weight aggregates of the amyloid-β-peptide (Aβ), so-called oligomers play a central role of the development of Alzheimer’s disease. One of the main techniques used to study them is fluorescence spectroscopy, for which peptides labeled with fluorescent tags are used. These tags are often covalently bound to the disordered N-terminus of the peptide assuming that hence they will not alter the aggregation process. However, we could find significant differences in the oligomer size distributions depending on the chosen dye. This talk will discuss the effect of four of the most commonly used fluorophores on the formation of oligomers of Aβ1-40.
Modulation of Amyloid b Peptide Aggregation by Hydrophilic Polymers
The origin of a number of neurodegenerative diseases, such as Alzheimer’s, Parkinson’s, and prion diseases, is associated with the fibrillation of amyloid peptides. It has been widely described in the literature that fibril formation in vitro strongly depends on experimental conditions such as pH, temperature, concentration, or additives, such as nanoparticles, other peptides and proteins, lipids, surfactants, and polymers. In this contribution, we monitor amyloid-b 1-40 peptide (Aβ40) fibril formation in a mixture with thermoresponsive poly(oligo(ethylene glycol)m acrylates), in which the polymer’s hydrophobicity is tuned by variation of the number of ethyleneglycol-units in the side-chain (m = 1-9). The polymers are prepared via RAFT-polymerization, obtaining a broad range of molecular weights (Mn = 1.5 to 35 kDa, polydispersity index PDI = 1.10 to 1.18) and tuneable cloud point temperatures (Tcp), ranging from 0 to 100 oC, respectively. The influence of the number of ethylene glycol units (m) within the polymer-backbone of (m = 1-9), allows to alter the hydrophilicity of these polymers, which is shown to modulate Aβ40 aggregation.