Table 1.
Compilation of reaction rate constants confirmed by independent studies
| Substrate | On/off rate | Value range* | Single-filament refs. | Other techniques refs. | |
| Actin monomers (Mg-ATP-actin) | Barbed end | On rate | 7–12 µM−1⋅s−1 | 18, 73, 84, 116 | 4, 117 |
| Profilin-actin (Mg-ATP-actin) | Barbed end | On rate | 6–9 µM−1⋅s−1 | 33, 56, 73, 116 | |
| Actin monomers (Mg-ADP-actin) | Barbed end | On rate | 3–5 µM−1⋅s−1 | 35 | 4, 117 |
| Actin subunit (Mg-ADP-actin) | Barbed end | Off rate | 4–12 s−1 | 34, 35, 76, 95, 99 | 4, 117 |
| Profilin-actin (Mg-ADP-actin) | Barbed end | Off rate | 52 s−1 | 72 | 118 |
| Actin monomers (Mg-ATP-actin) | Pointed end | On rate | 0.5–1.5 µM−1⋅s−1 | 34, 35 | 4 |
| Actin subunit (Mg-ADP-actin) | Pointed end | Off rate | 0.1–0.4 s−1 | 34, 35, 67, 68, 99 | 4, 119 |
| Pi (release from ADP-Pi-actin) | Within filament | Off rate | 2–7⋅10−3 s−1 | 35, 72 | 120, 121 |
| Profilin-actin (Mg-ATP-actin) | mDia1-bound barbed end | On rate | 40–60 µM−1⋅s−1 | 63, 73, 85, 122, 123 | |
| Bni1p-bound barbed end | On rate | 15–20 µM−1⋅s−1 | 73, 124 | ||
| Capping protein | Barbed end | On rate | 3–19 µM−1⋅s−1 | 29, 31, 34 | 125, 126 |
| Off rate | 3–11⋅10−4 s−1 | 28, 29, 31 | 125, 126 |
*Reported values from single-filament studies vary within the indicated range due to different experimental conditions: pH 7.0 to 7.8, with 50 to 100 mM KCl, at an unspecified “room temperature.”