Fig. 3.
The Zur-regulated genes zinT, znuA and rpmE2 are activated by Cu ions. The levels of transcription of each gene were determined by RT-PCR using samples obtained from the wild-type or the Δzur mutant strain grown in M9 medium after 40 min exposure to 10 µM CuSO4 (Cu) or 50 µM ZnSO4 (Zn), or without metal (–). After electrophoretic analysis of the amplification products the bands were quantified by densitometry (representative agarose gels are shown in Fig. S1). In each condition, the values were normalized against those of the housekeeping gene GAPDH. The graphs show the levels of transcription of zinT, znuA or rpmE2 obtained in each strain and condition, relative to the levels obtained in the wild-type strain with no metal added. Data correspond to mean values of three independent experiments performed in triplicate. Error bars depict sd.