Table 2.
Relationship between ADP release rate constant and in vitro sliding velocity.
| Myosin (HMM) | aMotility (nm/sec) | b1/ton(sec−1) | cADP Release (sec−1) |
|---|---|---|---|
| MV | 1199 ± 51 | 48 ± 2 | 36 ± 1 |
| SK | 7530 ± 810 | 1506 ± 162 | N.D. |
| SM | 513 ± 65 | 103 ± 13 | 213 ± 1 |
| NM | 253 ± 20 | 51 ± 4 | 56 ± 1 |
a
Measured in the in vitro motility assay at 35–36 °C.
b
The rate constant for detachment is based on the equation V = duni/ton, therefore 1/ton is the detachment rate constant. The value for (unitary displacement) duni was assumed to be 5 nm for SK, SM, and NM, and 25 nm for MV.
c
Measured in the stopped-flow at 35 °C. The fast phase of the fluorescence transients from dmantADP release is shown.