Effect of heparin on W7FW14F apomyoglobin at pH 4.0.

Panel A: Absorbance at 280 nm of supernatant solution in the absence (▪) and in the presence of 0.1 mg/mL heparin (•). Protein concentration was 40 µM. Points are experimental values, continues line was obtained from an exponential fit as A_{280 nm}(t) = A_{280 nm}(∞)+A₁ e^−kt. Panel B: Time-dependence of the far-UV CD spectra in the presence of 0.1 mg/mL heparin. From the lower to the upper spectrum, times are: 20, 40, 60, 120, 180, 300 and 360 min. The protein samples (40 µM) were diluted 1∶2 before spectra acquisition. In red is displayed the spectrum recorded in the absence of heparin. Panel C: ThT fluorescence in the absence (▪) and in the presence of 0.1 mg/mL heparin (•). Protein concentration was 40 µM. Other experimental details are reported under “Materials and Methods”.