Structural and Material Properties of Amyloid Aβ40/42 Fibrils

Mingyan Dong, Thomas J. Paul, Zachary Hoffmann, Kwaichow Chan, Dingkun Hu, Hongqi Ai, Rajeev Prabhakar

Research output: Contribution to journalArticle

4 Scopus citations

Abstract

In this study, structural and mechanical properties of a series of models of Aβ42 (one- and two-fold) and Aβ40 (two- and three-fold) fibrils have been computed by using all-atom molecular dynamics simulations. Based on calculations of the twist angle (θ) and periodicity (v=360d/θ), oligomers formed by 20, 11, and 13 monomers were found to be the smallest realistic models of three-fold Aβ40, one-fold Aβ42, and two-fold Aβ42 fibrils, respectively. Our results predict that the Aβ40 fibrils initially exist in two staggered conformations [STAG(+2) and STAG(+1)] and then undergo a [STAG(+2)→STAG(+1)] transformation in a size-dependent manner. The length of the loop region consisting of the residues 23–29 shrinks with the elongation of both Aβ40 and Aβ42 fibrils. A comparison of the computed potential energy suggests that a two-fold Aβ40 aggregate is more stable than its three-fold counterpart, and that Aβ42 oligomers can exist only in one-fold conformation for aggregates of more than 11 monomers in length. The computed Young′s modulus and yield strengths of 50 GPa and 0.95 GPa, respectively, show that these aggregates possess excellent material properties.

Original languageEnglish (US)
Pages (from-to)2558-2566
Number of pages9
JournalChemPhysChem
DOIs
StatePublished - Aug 18 2016

Keywords

  • conformation analysis
  • helical structures
  • materials science
  • mechanical properties
  • molecular dynamics

ASJC Scopus subject areas

  • Atomic and Molecular Physics, and Optics
  • Physical and Theoretical Chemistry

Fingerprint Dive into the research topics of 'Structural and Material Properties of Amyloid Aβ<sub>40/42</sub> Fibrils'. Together they form a unique fingerprint.

  • Cite this