Table 1 Summary of selected steady-state and transient kinetic parameters.
From: Load-dependent modulation of non-muscle myosin-2A function by tropomyosin 4.2
Parameter | Myosin construct | Method | No Tpm | Tpm4.2 | Fold change a |
|---|---|---|---|---|---|
kcat | NM-2A-HMM | NADH-coupled steady-state ATPase assay | 0.22 ± 0.03 s−1 | 0.34 ± 0.02 s−1 | 1.55 |
Kactin | NM-2A-HMM | NADH-coupled steady-state ATPase assay | 30 ± 12 μM | 29 ± 6 μM | – |
kcat | NM-2A-S1 | NADH-coupled steady-state ATPase assay | 0.16 ± 0.05 s−1 | 0.23 ± 0.06 μM | 1.44 |
Kactin | NM-2A-S1 | NADH-coupled steady-state ATPase assay | 77 ± 57 μM | 63 ± 55 μM | – |
Phosphate release from actomyosin b | NM-2A-S1 | Stopped-flow, MDCC-PBP | 0.084 ± 0.003 s−1 | 0.179 ± 0.012 s−1 | 2.13 |
ADP release from actomyosin | NM-2A-S1 | Stopped-flow, mant-ADP | 6.05 ± 0.25 s−1 | 5.29 ± 0.06 s−1 | 0.87 |
ADP release from actomyosin | NM-2A-HMM | Stopped-flow, mant-ADP | c 0.48 ± 0.07 s−1d 9.1 ± 2.2 s−1 | c 0.50 ± 0.07 s−1d 7.5 ± 2.0 s−1 | – |
