Publication Information

Basic Information

Access and Citation

AI Researcher Chatbot

Get quick answers to your questions about the article from our AI researcher chatbot

Primary Location

Authors

Topics

Keywords

Related Works

Title: $Secondary Conformations and Temperature Effect on Structural Transformation of Amyloid β(1–28),(1–40) and (1–42) Peptides
Abstract: Abstract Abstract Secondary structure of three amyloid β-peptides [Aβ(1–28), Aβ(1–40) and Aβ(1–42)] in the solid state was respectively determined by Fourier transform infrared (FT-IR) microspec- troscopy. Their thermal-dependent structural transformation were also investigated by FT- IR microspectroscopy equipped with a thermal analyzer. The present result demonstrates that the solid-state Aβ(1–28), Aβ(1–40) and Aβ(1–42) peptides showed a significant IR spectral difference in the amide I and II bands. The secondary conformation of Aβ(1–28) peptide was the combination of major β-sheet and minor α-helix with little random coil structures, but Aβ(1–40) peptide showed the co-existence of major β-sheet and minor random coil with little α-helix structures. Aβ(1–42) peptide mainly consisted of the predominant β-sheet structure. Although the intact Aβ(1–28), Aβ(1–40) or Aβ(1–42) peptide exhibits a different secondary structure, a similar β-conformation may form after thermal treatment. A thermal- dependent transition was found for solid Aβ(1–28) and Aβ(1–40) peptides near 40° C and 45° C, respectively. There was no transition temperature for solid Aβ(1–42) peptide, however, due to only a very little level of α-helix and random coil structure containing in the solid Aβ(1–42) peptide. The thermal denaturation plays an important role in the structural transformation from α-helix/random coil to β-sheet. Key words: amyloid β-peptide [Aβ(1–28),Aβ(1–40), and Aβ(1–42)]secondary structureFT-IRheatingconformational transformation