Table 1. Relative equilibrium-binding constants.

	Wild-type RNAP	Δflap RNAP	Ratio
σ70 Derivative	Relative Kb	Relative Kb	Flap-specific relative Kb
R541C/L607P	0.46 ± 0.03	1.2 ± 0.2	0.38
L607P	0.52 ± 0.07	0.96 ± 0.09	0.54
R541C	1.0 ± 0.2	1.8 ± 0.2	0.56
Wild-type	1.0	1.0	1.0
T544M	2.8 ± 0.3	1.1 ± 0.1	2.5
T544I	5.9 ± 0.4	1.1 ± 0.1	5.4
T544I/D581G	12 ± 4	1.0 ± 0.1	12