Table 1.

Kinetic and equilibrium constants of Arp2/3 complex for adenosine nucleotides at 25°C

Nucleotide	Arp2/3		Arp2/3 + N-WASP WA		Method
	koff (s−1)	Kd (μM)	koff (s−1)	Kd (μM)
ATP	2.6	0.5*	0.7	0.15*	Stopped flow
ATP (Arp2)		0.6		0.25	32P UV crosslinking
ATP (Arp3)		1.3		0.5	32P UV crosslinking
ADP	0.7	0.14*	0.3	0.06*	Stopped flow
EthenoATP		3.1		1.3	Fluorescence

^*Equilibrium constants calculated assuming k_on = 5 μM⁻¹s⁻¹ (34).