ITC profile for the binding of 1200 µM of (A) poly(dA-dT).poly(dA-dT), (B) poly(dA).poly(dT), (C) poly(dG-dC).poly(dG-dC) and (D) poly(dG).poly(dC) to harmalol (20 µM) at 25±0.5°C, pH 6.8.
Each heat burst curve (in the bottom part of upper panel) is the result of a 1.5 µL sequential injection of the polynucleotide into harmalol (curves at the bottom). The top part of upper panel show the heat burst for the injection of the polynucleotide into the same buffer as control in each experiment (curves offset for clarity). The lower panel represent the corresponding normalized heat data against the molar ratio (P/D) (E, F, G and H). The data points (•-•) reflect the experimental injection heats while the solid line represents the calculated best fit of the data. The values of the various thermodynamic parameters obtained are presented in Table 2.