Table 1.
Summary of measured and calculated parameters for in vitro model system.
| Data source | Experimental Condition | ||
|---|---|---|---|
| MLCK | Ca2+CaM-MLCK + ATP | ||
| State of SMM | SMM | pSMM | |
| Initial phosphorylation rate (kpo) | Figure 1 | - | 0.045% s−1 or 1.17 SMM heads s−1 MLCK−1 |
| Rate of loss of MLCK (kloSt) | Figure 1 | - | 0.22% s−1 |
| Average lifetimes (τon) in s and distributions in % |
Figure 7 | 1.09 ± 0.17 (36 ± 2%) 8.23 ± 0.48 (64 ± 2%) |
1.25 ± 0.06 (49 ± 2%) 12.39 ± 0.48 (51 ± 2 %) |
| Dissociation rate constants (k−1 for SMM and k+2 for pSMM) in s−1 |
Figure 7 | 0.92 (36%) 0.12 (64%) |
0.80 (49%) 0.08 (51%) |
| Association rate constants (k+1) (estimated) |
Figure 7 and Kd(a) | 0.24 s−1μM−1 for SMM <0.01 s−1μM−1 for pSMM |
|
| Association rate for Figure 1 (estimated) |
Figure 1, Figure 7 and Kd |
2.3 – 4.6 s−1 for SMM | |
(a)
Kd measured in solution with myosin filaments (3.8 and >60 μM for SMM and pSMM, respectively).