Table 1. Experimentally Determined Kinetic Values and Values Used in the Tenua Simulation.
| rate constant | AcsA-AcsB (measured) | AcsA-AcsB (steady-state simulation) | BcsA-BcsB (measured) | BcsA-BcsB (steady-state simulation) | BcsA-BcsB (processivity simulation) |
|---|---|---|---|---|---|
| k1, M–1 s–1 | 6100 | 200b | 600 | 10b | 3000 |
| k2, s–1 | nda | 0.035 | nd | 0.011 | 1.5 |
| k3, s–1 | 2.1 × 10–4 | 2.1 × 10–4 | 1.2 × 10–3 | 1.0 × 10–3 | 0.4 |
| k4c, s–1 | nd | 90 | nd | 16 | 5 |
| k5, M–1 s–1 | 5.0 × 105 | 5.0 × 105 | 2.0 × 104 | 2.0 × 104 | 1.4 × 106 |
| k6c, s–1 | 67 | 70 | 12 | 12 | 100 |
a
Not determined.
b
The experimental value is calculated from the slope of the Michaelis–Menten plot, as shown in Figure S1. The reaction of E in the unprimed form and in the primed form both contribute to this rate constant (kcat/Km) and thus is consistent with this value being higher than the simulated value.
c
The value for k4 for translocation is modeled to be not the rate-limiting step (see Discussion) and thus is provided a higher estimated value.