Table 2.

Kinetic rates, transition probability ratios (N_x→y / N_x,total), and partition ratios (Q) of GT-MutS binding, unbinding, and conformational transitions.

		(1)Transition rate (s−1)	(2)Nx→y / Nx,total	(3)Q = kf / kr
GT-MutS complex transitions	U to B	0.38	0.56	15
	B to U	0.026	0.42
	U* to B	0.59	0.45	95
	B to U*	0.0062	0.099
	I to B	0.039	0.25	14
	B to I	0.0027	0.043
	B* to B	0.10	0.15	53
	B to B*	0.0019	0.030
	B to SB	0.0039	0.063	0.28
	SB to B	0.014	0.19
	U to SB	0.15	0.22	6.8
	SB to U	0.022	0.31
	U* to SB	0.45	0.34	38
	SB to U*	0.012	0.17
	U to U*	0.0094	0.014	0.12
	U* to U	0.077	0.059
	I to SB	0.028	0.18	4.5
	SB to I	0.0062	0.087
	B* to SB	0.16	0.23	21
	SB to B*	0.0075	0.10
	U to I	0.047	0.07	2.5
	I to U	0.019	0.12
	U to B*	0.036	0.053	0.21
	B* to U	0.17	0.25
	U* to B*	0.028	0.021	0.8
	B* to U*	0.035	0.052
	I to B*	0.0054	0.034	nd
	B* to I	nd
				KA (M−1)
4MutS Binding/ Unbinding transitions	free to U	0.041	0.096	3.8 × 106
	U to free	0.054	0.081
	free to U*	0.019	0.043	5.3 × 105
	U* to free	0.18	0.13
	free to I	0.052	0.12	4.0 × 106
	I to free	0.065	0.42
	free to B*	0.049	0.11	1.2 × 106
	B* to free	0.21	0.31
	free to B	0.25	0.58	5.7 × 107
	B to free	0.022	0.35
	free to SB	0.020	0.046	1.3 × 107
	SB to free	0.0098	0.14

¹Transition rates are determined from the kinetic branching equations shown in Eq. 2 – Eq. 7

²Transition probability ratios were determined by the ratio of the number of times a given transition occurred versus the total number of transitions recorded from that state in total.

³Partition ratios for each transition were calculated by the ratio of the forward and reverse rates and were used to calculate the relative free energies between each state (Supplemental Information).

⁴Association constants for the binding and unbinding transitions are determined at a MutS concentration of 200 nM. These values result in an average dissociation constant of 13 nM, consistent with the dissociation constant determined in the bulk by fluorescence anisotropy (40 nM) (4).