Table 2. Thermodynamic parameters for metal–apo PA4063 interaction as assayed by ITC.

Ligand	No. of binding sites	K d (µM)	ΔG (kcal mol−1)	ΔH (kcal mol−1)	−TΔS (kcal mol−1)
Zn2+	2.08 ± 0.29	1.91 ± 0.42	−7.83 ± 0.64	−6.71 ± 0.17	−1.11 ± 0.53
Co2+	1.85 ± 0.02	4.27 ± 0.37	−7.33 ± 0.19	−5.40 ± 0.05	−1.94 ± 0.13