Figure 2.
ArsR2 is a metal-binding protein. (A) qRT-PCR of arsR2 transcript levels in Brucella S2308 and A19 in the presence or absence of Cu (II) or Fe (III). Bacteria were grown in TSB medium to OD600 0.6 and incubated with metal ions for 1 h before RNA isolation. Data represent mean and standard deviation. **<0.01 by unpaired two-tailed t tests with Welch’s correction. (B) Absorption spectra of ArsR2 (50 μg/mL) after incubation in different concentrations of Cu (II) or Fe (III). (C) Interactions between ArsR2 and Cu (II) and Fe (III) analyzed by MST. Kd represents the dissociation constant.