Table 1:

Summary of rate and equilibrium constants measured for Myo5 in this study. Errors are standard errors of the fits.

	Phosphorylated Myo5	Unphosphorylated Myo5
Steady-state actin-activated ATPase
$V_{\max }\left({\text{s}}^{-1}\right)$	3.3 (± 0.15)	ND
$K_{\text{ATPase}}\left(\text{μM}\right)$	5.1 (± 0.88)	ND
ATP binding
${K_1}^{\prime }\left({\text{μM}}^{-1}\right)$	ND	0.006 (± 0.0016)
${k_{+2}}^{\prime }\left({\text{s}}^{-1}\right)$	≥ 335	290 (± 24)
${K_1}^{\prime }{k_{+2}}^{\prime }\left({\text{μM}}^{-1}{\text{s}}^{-1}\right)$ a	0.39 (± 0.017)b	1.1 (± 0.28)c
ADP release
${k_{+5}}^{\prime }\left({\text{s}}^{-1}\right)$	74 (± 2.0)	107 (± 5.9)

^aDetermined from a linear fit of the unbinding rates.

^bLinear fit of all data for Phosphorylated Myo5 in Fig. 2E.

^cLinear fit of observed rates below 100 µM ATP for Unphosphorylated Myo5 in Fig 2E. ND: Not Determined.