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Table 2 Kd and kpol for incorporation and misincorporation by mutant RNA polymerase (RNAP)

From: Stepwise mechanism for transcription fidelity

  cGTP incorporation ncGTP misincorporation
RNAP kpol (s-1) Kd (μM) kpol (s-1) Kd (μM)
WT/Stl 3.6 ± 0.2 × 10-3 24 ± 6 1.1 ± 0.4 × 10-4 710 ± 70
H1242A 9.8 × 10-1 20 1.7 ± 0.2 × 10-3 2300 ± 500
R1239A 2.1 20 2.7 ± 0.3 × 10-3 2700 ± 500
H1242A/R1239A 6.9 ± 0.5 × 10-2 37 ± 11 4.0 ± 0.4 × 10-4 2900 ± 500
M1238A 5.6 ± 0.5 × 10-2 47 ± 17 3.6 ± 0.3 × 10-4 990 ± 230
  1. Incorporation of cGTP was studied in ECG1, misincorporation of ncGTP - in ECA. Kd and kpol (reaction rate at saturating nucleotide triphosphate concentration) for incorporation by R1239A and H1242A RNAPs were obtained by fitting the kinetics data into a simple kinetic model as described in Additional File 1: Supplementary Methods. Kd and kpol for incorporation by other RNAPs and misincorporation by all RNAPs was obtained by fitting into the Michaelis-Menten equation as described in Materials and Methods. Errors are the standard error of data fitting. The values were rounded to two significant digits.