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Abstract Amyloid‐beta (Aβ) peptides, primarily Aβ40 and Aβ42, are central to the formation of amyloid plaques, a pathological hallmark of Alzheimer's disease (AD). These peptides, derived from the amyloid precursor protein (APP), are aggregation prone and neurotoxic. Experimental studies aimed at understanding Aβ aggregation and interaction require pure, monomeric peptides with the native sequences, including the absence of an N‐terminal methionine. We present an optimized protocol for producing recombinant human Aβ40 and Aβ42 using a SUMO fusion system inEscherichia coli. Cleavage of the SUMO tag enables recovery of native‐sequence peptides, producing physiologically relevant monomers with high yield and purity. This method eliminates the need for chemical synthesis and offers a reliable and cost‐effective approach to producing recombinant Aβ suitable for aggregation studies, structural analyses, and interaction assays. The resulting peptides closely mimic endogenous Aβ, facilitating accurate models of Alzheimer's disease pathogenesis and supporting future therapeutics development. © 2025 The Author(s). Current Protocols published by Wiley Periodicals LLC. Basic Protocol: Expression and purification of Aβ40 and Aβ42 fromEscherichia coli
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Molecular basis for chirality-regulated Aβ self-assembly and receptor recognition revealed by ion mobility-mass spectrometry
Abstract Despite extensive efforts on probing the mechanism of Alzheimer’s disease (AD) and enormous investments into AD drug development, the lack of effective disease-modifying therapeutics and the complexity of the AD pathogenesis process suggest a great need for further insights into alternative AD drug targets. Herein, we focus on the chiral effects of truncated amyloid beta (Aβ) and offer further structural and molecular evidence for epitope region-specific, chirality-regulated Aβ fragment self-assembly and its potential impact on receptor-recognition. A multidimensional ion mobility-mass spectrometry (IM-MS) analytical platform and in-solution kinetics analysis reveal the comprehensive structural and molecular basis for differential Aβ fragment chiral chemistry, including the differential and cooperative roles of chiral Aβ N-terminal and C-terminal fragments in receptor recognition. Our method is applicable to many other systems and the results may shed light on the potential development of novel AD therapeutic strategies based on targeting the D-isomerized Aβ, rather than natural L-Aβ.
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- Award ID(s):
- 1710140
- PAR ID:
- 10153775
- Publisher / Repository:
- Nature Publishing Group
- Date Published:
- Journal Name:
- Nature Communications
- Volume:
- 10
- Issue:
- 1
- ISSN:
- 2041-1723
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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