Using EM), we find A β fibrils in the presence of IgG2b; however, a mixture of A β fibrils and nonfibrillar amorphous A β structures was observed in the presence of 72D9.
Electron microscopic examination of this preparation demonstrated it to be a mixture of mainly Aβ1-42 fibrils, and some oligomers (data not shown).
We conclude that aggregation of p53 into a mixture of oligomers and fibrils sequesters the native protein into an inactive conformation that is typical of a prionoid.
A solution containing a mixture of MstnPP protofibrils and fibrils, as well as lower concentrations of soluble aggregates and protofibrils, had a reduced effect.
ThT binding assays were carried out on the MstnPP aggregates and compared to a solution containing a mixture of insulin protofibrils and fibrils as a positive control.
Tyramine and 2-amino-4-tert-butylphenol revealed a mixture of both mature and intermediate fibrils (Figure 5F and G), whereas 4- 2-aminoethylaniline) revealed a mixture of all fibril sizes (Figure 5C).
After one week at 60°C, ThT fluorescence had increased significantly in the pH 5.3 solution (Fig. 4A), which contained a mixture of prefibrillar aggregates and amyloid fibrils observed by TEM (Fig. 4B 4F) in both the presence and absence of 0.1% sodium azide.
To form fibrils, a mixture of 0.5 mg/ml rPrP with 50 mM MES, pH 6.0, and 2.0 M or 0.5 M guanidine hydrochloride (GdnHCl) was incubated at 37 °C under continuous agitation.
When we incubated monomeric Aβ42 at 1 mg ml−1 in 50 mM Tris-HCl, pH 7.4, and 1 mM EDTA at 25°C, we found, consistent with previous observations (Walsh et al, 1999; Bitan and Teplow, 2004; Klyubin et al, 2005), that neurotoxicity of forward protofibrils peaked between 24 and 48 h, at which point the sample contains a mixture of protofibrils and some mature fibrils.
However, differences in higher order packing effects or spacer length may result in self-sorting and the formation of fibrils containing non-statistical mixtures of gelators or even independent networks.
