Table 1.

Trigger loop affects catalysis, NTP binding, and translocation equilibrium. Global fit parameters (errors as SD) obtained from modeling of F-v curves in Fig. 3 to the two-binding site Brownian ratchet model of Fig. 2C.

	WT	E1103G	H1085A/E1103G
kcat	34 ± 2 s-1	56 ± 2 s-1	6 ± 1 s-1
	77 ± 3 s-1	77 ± 3 s-1	22 ± 2 s-1
KD	140 ± 16 μM	49 ± 6 μM	94 ± 17 μM
Kδ	0.2 ± 0.1	0.8 ± 0.1	0.3 ± 0.1
δ	0.34 nm (fixed)	0.34 nm (fixed)	0.34 nm (fixed)