FTIR reveals structural differences between native beta-sheet proteins and amyloid fibrils.
The presence of beta-sheets in the core of amyloid fibrils raised questions as to whether or not beta-sheet-containing proteins, such as transthyretin, are predisposed to form such fibrils. However, we show here that the molecular structure of amyloid fibrils differs more generally from the beta-sheets in native proteins. This difference is evident from the amide I region of the infrared spectrum and relates to the distribution of the phi/psi dihedral angles within the Ramachandran plot, the average number of strands per sheet, and possibly, the beta-sheet twist. These data imply that amyloid fibril formation from native beta-sheet proteins can involve a substantial structural reorganization.
Zandomeneghi
Giorgia
G
Institut für Molekulare Biotechnologie (IMB), D-07745 Jena, Germany.
Krebs
Mark R H
MR
McCammon
Margaret G
MG
Fändrich
Marcus
M
D000682:Amyloid / Q000737:chemistry*; D006801:Humans; D011228:Prealbumin / Q000737:chemistry; D017433:Protein Structure, Secondary; D017550:Spectroscopy, Fourier Transform Infrared
D000682:Amyloid; D011228:Prealbumin