Related Experiment Video

Updated: Jan 18, 2026

Characterization of pH-Dependent Reversible Self-Assembly of Amyloid Beta 1-40-Coated Gold Colloids
08:53

Characterization of pH-Dependent Reversible Self-Assembly of Amyloid Beta 1-40-Coated Gold Colloids

Published on: March 21, 2025

1.2K

The structure of amyloid-β (1-42) oligomers in membrane-mimetic environments

Oleksandra Kurysheva1, Nina Mann1, Uliana Afonina1

  • 1Department of Biochemistry and Biophysics, Stockholm University, Sweden.

Spectrochimica Acta. Part A, Molecular and Biomolecular Spectroscopy
|September 7, 2025
PubMed

Insights

Amyloid-beta 42 (Aβ42) oligomers maintain their beta-sheet structure in membrane environments, unlike Aβ40. This stability, due to rapid aggregation, suggests aqueous models are relevant for Aβ42

Area of Science:

  • Biochemistry
  • Neuroscience
  • Structural Biology

Background:

  • Alzheimer's disease is characterized by amyloid-beta (Aβ) peptide aggregation.
  • Lipid interactions with Aβ40 are well-studied, but Aβ42 interactions with membranes are less understood.
  • Understanding Aβ42 aggregation is crucial for Alzheimer's disease research.

Purpose of the Study:

  • To investigate the structural behavior of Aβ42 oligomers in membrane-mimicking environments.
  • To compare the interaction of Aβ42 with zwitterionic (POPC) and anionic (POPG) lipid vesicles.
  • To determine the relevance of aqueous Aβ42 models in biological membrane contexts.

Main Methods:

  • Time-resolved infrared spectroscopy to monitor Aβ42 structure.
  • Use of POPC and POPG lipid vesicles as membrane mimics.
  • Isotope-edited infrared spectroscopy to identify residue locations within beta-sheets.
  • Comparison with detergent (SDS) interactions.

Main Results:

  • Aβ42 oligomers retain their beta-sheet structure in both POPC and POPG vesicle environments.
  • Lipid presence has minimal effect on Aβ42 beta-sheet structure, except during initial oligomerization at low temperatures.
  • The V18 residue is consistently located in beta-sheets, irrespective of lipid presence.
  • Unlike SDS, model membranes do not prevent V18 inclusion in stable beta-sheets.
  • Aβ42's rapid aggregation leads to less membrane interaction compared to Aβ40.

Conclusions:

  • Aβ42 oligomer structure in aqueous solution is relevant even in the presence of biological membranes.
  • The distinct aggregation properties of Aβ42 influence its membrane interaction.
  • Model membranes (POPC, POPG) provide a more accurate representation of Aβ42 interactions than SDS.
Keywords:
Alzheimer's diseaseAmyloid-β peptideFTIR spectroscopyInfrared spectroscopyIsotope-edited FTIR spectroscopyMembrane

More Related Videos

A Tailored HPLC Purification Protocol That Yields High-purity Amyloid Beta 42 and Amyloid Beta 40 Peptides, Capable of Oligomer Formation06:34

A Tailored HPLC Purification Protocol That Yields High-purity Amyloid Beta 42 and Amyloid Beta 40 Peptides, Capable of Oligomer Formation

Published on: March 27, 2017

12.4K
Interactions with and Membrane Permeabilization of Brain Mitochondria by Amyloid Fibrils15:04

Interactions with and Membrane Permeabilization of Brain Mitochondria by Amyloid Fibrils

Published on: September 28, 2019

6.3K

Related Concept Videos

Amyloid Fibrils03:03

Amyloid Fibrils

Amyloid fibrils are aggregates of misfolded proteins.  Under most circumstances, misfolded proteins are either refolded by chaperone proteins or degraded by the proteasome. However, in the case of a mutation or a disease, these proteins can accumulate to form large clusters and often further assemble to form elongated fibers, called fibrils. 
Amyloid deposits were observed as early as 1639 in the liver and the spleen.   In 1854, Rudolph Virchow performed iodine staining,...
11.7K
Amyloid Fibrils03:03

Amyloid Fibrils

6.3K
Mechanisms of Membrane Domain Formation00:59

Mechanisms of Membrane Domain Formation

Different physical properties of lipids and proteins allow them to localize and form distinct islands or domains in the membrane. Some membrane domains are formed due to protein-protein interactions, whereas others are formed due to the presence of specific lipids such as sphingolipids and sterols—for example, large proteins, such as bacteriorhodopsin, aggregate and create distinct domains.
Another mechanism for membrane domain formation involves membrane proteins interacting with...
3.8K
Assembly of the Lipid Bilayer in the ER01:28

Assembly of the Lipid Bilayer in the ER

Biological membranes are more than just a barrier separating cell cytoplasm from the outside environment. They are highly dynamic and help maintain the integrity and physiological stability of the cells as well as membrane-bound organelles. Membranes also play vital roles in cell-to-cell and intracellular communication.
A large chunk of any biological membrane is composed of phospholipids. These lipids have a heterogeneous distribution across different subcellular organelles and even between...
4.0K
Asymmetric Lipid Bilayer01:35

Asymmetric Lipid Bilayer

Biological membranes show uneven distribution of different types of lipids in the inner and outer layers, resulting in transverse asymmetric membranes. The treatment of the erythrocyte membrane with the enzyme phospholipase confirmed the asymmetric nature of the lipid bilayer. The enzyme hydrolyzes lipids into fatty acids and hydrophilic groups. The phospholipase acts only on the outer layer of the membrane, while the inner layer remains intact. The phospholipase treatment resulted in 80%...
9.6K
Biosynthesis of Lipids01:29

Biosynthesis of Lipids

Microbial membranes exhibit remarkable diversity in lipid composition, reflecting evolutionary adaptations to various environmental conditions. The three domains of life—Bacteria, Archaea, and Eukarya—synthesize membrane lipids through distinct biosynthetic pathways, leading to fundamental structural differences that impact membrane stability, function, and adaptability.Fatty Acid-Based Lipids in Bacteria and EukaryaBacteria and eukaryotes share a common fatty acid biosynthesis...
537