Mutation of the Phe20 residue in Alzheimer's amyloid beta-peptide might decrease its toxicity due to disruption of the Met35-cupric site electron transfer pathway

Chem Res Toxicol. 2004 Mar;17(3):325-9. doi: 10.1021/tx030044w.

Abstract

It has been proposed that the Met residue in the C-terminal domain of the Alzheimer's disease beta-amyloid peptide (betaA) serves as a source of electrons for the Cu(II)-catalyzed reduction of molecular oxygen to hydrogen peroxide. Mechanistically, this process would require the long distance electron transfer from the thioether sulfur to the peptide-bound copper. Therefore, the electron transfer pathways between the Met35 sulfur atom and the cupric site in the N terminus of betaA congeners have been analyzed applying semiclassical models of long distance electron transfer. Simulations performed for several betaA conformers collected along the 6 ns Langevin Dynamics trajectories suggest that the presence of the Phe20 residue in the peptide is required for feasibility of the electron transfer. Thus, I would like to propose the mutation Phe20Ala in betaA as a potential way to reduce its neurotoxicity.

Publication types

  • Review

MeSH terms

  • Alzheimer Disease / genetics*
  • Amyloid beta-Peptides / genetics*
  • Copper / metabolism*
  • Electron Transport*
  • Humans
  • Methionine / metabolism*
  • Models, Molecular
  • Mutation*
  • Oxidation-Reduction
  • Peptide Fragments / metabolism
  • Phenylalanine / genetics*

Substances

  • Amyloid beta-Peptides
  • Peptide Fragments
  • Phenylalanine
  • Copper
  • Methionine