Table 1

Restoration of reduced SoxR [2Fe–S2] centers by chemical reduction after PQ treatment

SamplesReduced [2Fe–S2] clusters,* μM
ControlPQ-treated
Directly frozen0.35  ±  0.04<0.05
Thawed and dithionite-treated0.33  ±  0.050.32  ±  0.07
  • Strain XA90 containing pKOXR was treated with PQ as described for Fig. 2 and samples frozen for EPR measurement (Directly frozen). After the EPR measurements, samples were thawed at room temperature, dithionite was added to a final concentration of 1 mM (from a 100 mM stock), and the EPR measurements repeated (Thawed and dithionite-treated). The values shown are the means ± SD for three independent experiments. 

  • * Calculated from the gy amplitude.