Related Experiment Video
Updated: Jan 7, 2026
Characterization of pH-Dependent Reversible Self-Assembly of Amyloid Beta 1-40-Coated Gold Colloids
Published on: March 21, 2025
Insertion of β-barrel amyloid (25-35) oligomers in lipid bilayers: a molecular dynamics study
Tu Ni1,2, Kedong Bi1,2, Yujuan Wang1,2
1Jiangsu Key Laboratory for Design and Manufacture of Micro-Nano Biomedical Instruments, School of Mechanical Engineering, Southeast University, Nanjing, China.
Abstract:
Amyloid β (Aβ) peptides, particularly the toxic fragment Aβ25-35, disrupt lipid bilayers by forming ion channels or inserting into the membrane, which is a key factor in the pathogenesis of Alzheimer's disease. In this study, molecular dynamics simulations were employed to investigate the insertion behavior of β-barrel Aβ25-35 oligomers in a 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC)/1-palmitoyl-2-oleoyl-sn-glycero-3-phosphoglycerol (POPG) membrane. The results demonstrate that embedding the oligomer at a deeper position can enhance the stability of the barrel, and deprotonation of the LYS residue can notably influence its mobility within the membrane and interactions with lipids. During insertion, the protein barrel disrupts local lipid distribution and causes regional thinning of the membrane, but does not affect the overall membrane structural stability. These findings provide a deeper understanding of Aβ-induced membrane disruption mechanisms and offer insights into the membrane-associated pathogenic mechanisms of Aβ25-35 in the context of Alzheimer's disease.
Insights
Amyloid beta (Aβ) oligomers disrupt cell membranes, a key factor in Alzheimer's disease. Simulations show deeper insertion enhances stability, while LYS deprotonation affects Aβ mobility and lipid interactions.
Area of Science:
- Biochemistry
- Neuroscience
- Computational Biology
Background:
- Amyloid beta (Aβ) peptides, especially Aβ25-35, are implicated in Alzheimer's disease pathogenesis.
- Aβ peptides disrupt lipid bilayers, potentially forming ion channels or inserting into membranes.
Purpose of the Study:
- To investigate the insertion behavior of β-barrel Aβ25-35 oligomers into a model membrane using molecular dynamics simulations.
- To understand the impact of oligomer insertion depth and residue deprotonation on membrane structure and Aβ stability.
Main Methods:
- Molecular dynamics simulations were performed on Aβ25-35 oligomers within a POPC/POPG lipid bilayer.
- Analysis focused on oligomer insertion, stability, lipid interactions, and membrane structural changes.
Main Results:
- Deeper embedding of the Aβ25-35 oligomer enhanced its structural stability within the membrane.
- Deprotonation of Lysine (LYS) residues significantly altered the oligomer's mobility and lipid interactions.
- Oligomer insertion caused local lipid redistribution and membrane thinning but did not compromise overall membrane stability.
Conclusions:
- The study provides detailed insights into the membrane insertion mechanisms of Aβ25-35 oligomers.
- Findings elucidate the role of Aβ-membrane interactions in Alzheimer's disease pathogenesis.
- Understanding these interactions may inform therapeutic strategies targeting Aβ-induced neurotoxicity.
More Related Videos
15:04Interactions with and Membrane Permeabilization of Brain Mitochondria by Amyloid Fibrils
Published on: September 28, 2019
07:31Author Spotlight: Advancing Cell Membrane Biophysics - Exploring Interactions and Challenges Through Experimental and Computational Approaches
Published on: September 1, 2023
Related Concept Videos
03:03Amyloid Fibrils
Amyloid deposits were observed as early as 1639 in the liver and the spleen. In 1854, Rudolph Virchow performed iodine staining,...
03:03Amyloid Fibrils
01:09Multi-pass Transmembrane Proteins and β-barrels
α-Helix containing multi-pass transmembrane proteins
Multi-pass transmembrane proteins such as...