Table 1.
Actomyosin Kinetic Rate Constants with and without Ficoll70
| Kinetic Step | No Ficoll70 | With Ficoll70 |
|---|---|---|
| Actomyosin dissociation, K′1k′+2, μM−1s−1 | 1.247 ± 0.177 | 0.094 ± 0.089 |
| Actomyosin dissociation, Vmax, s−1 | 431.6 ± 120.1 | 9.4 ±1.4 |
| ATP binding to myosin, K1k+2, μM−1s−1 | 0.26 ± 0.05 | 0.11 ± 0.01 |
| Recovery stroke and hydrolysis, Vmax, s−1 | 34.9 ± 4.4 | 10.0 ± 0.9 |
| Weak-to-strong-binding transition, K8k′+4, μM−1s−1 | 0.13 ± 0.01 | 0.05 ± 0.01 |
| ADP release from actomyosin, K′5, μM | 1.07 ± 0.07 | 1.58 ± 0.58 |
| Basal myosin ATPase, (mole Pi)/(mole myosin)/s | 0.140 ± 0.007 | 0.133 ± 0.002 |
| Actin-activated myosin ATPase, Vmax, (mole Pi)/(mole myosin)/s |
2.5 ± 0.1 | 3.1 ± 0.1 |
| Actin activation, actin-activated/basal ATPase | 17.9 ± 1.1 | 23.3 ± 0.8 |