Fig. 3
From: Designed α-sheet peptides suppress amyloid formation in Staphylococcus aureus biofilms
CD measurements capture structural transitions of PSMα1. a CD spectra of PSMα1 samples (30 μM, 1.3% HFIP, 50 mM potassium phosphate buffer, pH 5.5) were taken periodically during aggregation. At early time points (t = 0, 48, 84 h), negative peaks at ~208 and ~220 nm represent α-helical secondary structure. At intermediate time points (t = 130 h), featureless spectra indicate formation of α-sheet, and by the end of the time course (t = 188 h) a negative peak at ~218 nm signals the presence of β-structure. b Close-up view of characteristic CD spectra for α-helix (0 h, purple), α-sheet (red, 130 h), and β-sheet (green, 188 h). c Aggregation of synthetic PSMα1 peptide (30 μM, same conditions as for CD) was tracked over time by ThT fluorescence in a microtiter plate. Error bars in c represent the standard deviation of the mean of four samples
