Abstract
Formation of the intermolecular β-sheet is a key event in the aggregation of 42-residue amyloid-β (Aβ42). We have recently identified a physiological and toxic conformer, the turn positions of which are slightly different from each other, in the aggregates of E22K-Aβ42 (one of the mutants related to cerebral amyloid angiopathy). However, it remains unclear whether the intermolecular β-sheet in the E22K-Aβ42 aggregates is parallel or antiparallel. We prepared an equal mixture of E22K-Aβ42 aggregates labeled at Cα and those labeled at C=O with 13C, whose intermolecular 13C-13C distance was estimated by solid-state NMR using rotational resonance (R2). The intermolecular proximity of β-strands at positions 21 and 30 was less than 6 Å, supporting the existence of the intermolecular parallel β-sheet in the E22K-Aβ42 aggregates as well as in wild-type Aβ42 aggregates. The results also suggest that each conformer would not accumulate alternately, but form a relatively large assembly.
Original language | English |
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Pages (from-to) | 2170-2175 |
Number of pages | 6 |
Journal | Bioscience, Biotechnology and Biochemistry |
Volume | 72 |
Issue number | 8 |
DOIs | |
Publication status | Published - 2008 |
Keywords
- Alzheimer's disease
- Aβ42
- Intermolecular parallel β-sheet
- Italian mutation
- Solid-state NMR
ASJC Scopus subject areas
- Biotechnology
- Analytical Chemistry
- Biochemistry
- Applied Microbiology and Biotechnology
- Molecular Biology
- Organic Chemistry