Fig. 2.

Effects of αΔ235 or αR265A on association of RNAP with the lacUV5 promoter. (A) Double reciprocal (τ) plots (see text) from reactions at a range of RNAP concentrations with the -130 to +40 fragment at 30°C. Wild-type reconstituted RNAP (•), αΔ235 RNAP (⋄), and αR265A RNAP (▾) are indicated. (B) Kinetic constants derived from the data shown in A (asterisks) or from nonlinear analysis of the same data (no asterisks; see also Fig. 9). Data from αR265A RNAP could not be fit for nonlinear analysis.