TABLE 1.
Isothermal titration calorimetry of IutA and IutE with Mn2+ and Zn2+
| Parameter | Valuea for: |
|||
|---|---|---|---|---|
| Mn2+ |
Zn2+ |
|||
| IutA | IutE | IutA | IutE | |
| Kd1 (nM) | 1.1 ± 0.5 | 2 ± 1 | 350 ± 40 | 70 ± 30 |
| ΔH1 (kJ/mol) | −17.7 ± 0.5 | −18 ± 1 | −55 ± 1 | −34 ± 5 |
| ΔS1 (J/mol · K) | 112 | 106 | −62 | 24.5 |
| Stoichiometry | 0.98 ± 0.01 | 1.01 ± 0.01 | 1.023 ± 0.005 | 1.01 ± 0.01 |
| ΔG1 (kJ/mol) | −51 | −50 | −37 | −41 |
| Kd2 (μM) | 0.2 ± 0.1 | 0.7 ± 0.3 | 6 ± 3 | |
| ΔH2 (kJ/mol) | 3.1 ± 0.5 | 6 ± 4 | −58 ± 25 | |
| ΔS2 (J/mol · K) | 137 | 136 | −94 | |
| Stoichiometry | 1.06 ± 0.08 | 1.1 ± 0.2 | 5.2 ± 0.2 | |
| ΔG2 (kJ/mol) | −38 | −35 | −30 | |
a
The errors reported for Kd, ΔH, and stoichiometry were obtained from ITC data-fitting software, whereas the errors for ΔG and ΔS were derived from Kd and ΔH error values.