Effect of C-terminal residues of Aβ on copper binding affinity, structural conversion and aggregation

PLoS One. 2014 Mar 3;9(3):e90385. doi: 10.1371/journal.pone.0090385. eCollection 2014.

Abstract

Many properties of Aβ such as toxicity, aggregation and ROS formation are modulated by Cu2+. Previously, the coordination configuration and interaction of Cu2+ with the Aβ N-terminus has been extensively studied. However, the effect of Aβ C-terminal residues on related properties is still unclear. In the present study, several C-terminus-truncated Aβ peptides, including Aβ1-40, Aβ1-35, Aβ1-29, Aβ1-24 and Aβ1-16, were synthesized to characterize the effect of Aβ C-terminal residues on Cu2+ binding affinity, structure, aggregation ability and ROS formation. Results show that the Aβ C-terminal residues have effect on Cu2+ binding affinity, aggregation ability and inhibitory ability of ROS formation. Compared to the key residues responsible for Aβ aggregation and structure in the absence of Cu2+, it is more likely that residues 36-40, rather than residues 17-21 and 30-35, play a key role on the related properties of Aβ in the presence of Cu2+.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amyloid beta-Peptides / chemistry
  • Amyloid beta-Peptides / metabolism*
  • Amyloid beta-Peptides / ultrastructure
  • Circular Dichroism
  • Copper / metabolism*
  • Electron Spin Resonance Spectroscopy
  • Microscopy, Electron, Transmission
  • Protein Structure, Secondary
  • Reactive Oxygen Species / metabolism
  • Spectrometry, Fluorescence

Substances

  • Amyloid beta-Peptides
  • Reactive Oxygen Species
  • Copper

Grants and funding

This work was supported by grants from National Science Council of Taiwan, ROC (NSC101-2627-M-715-001 and NSC102-2627-M-715-002 to YCC) and MacKay Medical College, Taiwan (B1011B05 to YCC). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.