Figure 3. The effects of metal ions on the DNA-binding activity of Rv2034.

(A) EMSA assays with or without metal ions. The Rv2034p DNA substrate was incubated with various amounts of the Rv2034 protein (0, 0.1, 0.2, 0.3, 0.4, and 0.5 µM) with or without 1 mM metal ions, as indicted on the top. (B) β-galactosidase activity was measured in M. smegmatis mc² 155 containing the pMZ1 and pMZ2 reporter plasmids. Cells were cultured with no metal supplement or maximum permissive concentrations of Zn(II) (70 µM), Ni(II) (35 µM), Co(II) (15 µM), Cd(II) (75 µM), Pb(II) (10 µM), Cu(II) (50 µM), or Mn(II) (0.75 µM).