Fig. 8.
Congo red binding assay for unglycosylated (PrPUP) and glycosylated (PrPGP) prion protein after incubation for 24 h in 1 mM phosphate buffer (pH 7.5) with (A) and without (B) DTT. Congo red (dotted lines), PrPUP (dashed line) and PrPGP (solid line). Although the spectra were subtracted by the peptide aggregates, the high baselines are the result of the heterogeneous nature of the peptide suspensions. (Inset) Photos of congo red samples after titrating the peptides that have been incubated for 24 h with or without DTT, respectively. CR, Congo red without peptide; UP, PrPUP; GP, PrPGP.