TABLE 2.
Kinetic, binding, and inhibition parameter values for the M. tuberculosis Ddl enzyme
| Parameter (ligand) | Value (mM) | Conditionsa |
|---|---|---|
| Kd1 (d-Ala) | 9.49 × 10−6 | E |
| Kd1 (d-Ala) | 6.15 × 10−6 | E + (5 mM) ATP-γS |
| Kd2 (d-Ala) | 1.17 | E |
| Kd2 (d-Ala) | 9.70 × 10−1 | E + (5 mM) ATP-γS |
| Kd1 (DCS) | 7.86 × 10−6 | E |
| Kd1 (DCS) | 4.71 × 10−6 | E + (5 mM) ATP-γS |
| Kd2 (DCS) | 9.90 × 10−1 | E |
| Kd2 (DCS) | 5.30 × 10−1 | E + (5 mM) ATP-γS |
| Kd (ATP) | 1.43 × 10−2 | E |
| IC50 (DCS) | 3.70 × 10−1 | E + 1.0 mM d-Ala + 6.0 mM ATP |
| IC50 (DCS) | 8.0 × 10−1 | E + 1.0 mM d-Ala + 0.5 mM ATP |
| IC50 (DCS) | 1.00 | E + 20.0 mM d-Ala + 6.0 mM ATP |
| IC50 (DCS) | 2.50 | E + 20 mM d-Ala + 0.5 mM ATP |
a
E (Ddl enzyme) was used at 3 μM for all fluorescence binding assays, 40 μM for the isothermal titration calorimetry, and 0.25 μM (10 μg/ml) in the kinetics assays as described in Materials and Methods.