Figure 4

Oxidation promotes OhrR dimerisation and inactivation. (A) OhrR purified protein (20 nmoles) was incubated for 15 min with CuOOH (0.55 nM ) or H₂O₂ (0.5 nM ) and then, when indicated, added with 0.5 mM DTT and incubated for another 15 min. (B) The DNA fragment (20 pmoles) corresponding to ohr-ohrR intergenic region was incubated with purified OhrR protein (20, 50 or 100 pmoles) in the presence of 0.5 nM H₂O₂ and in the absence or in the presence of 0.5 mM DTT.