Figure 6.

Translation of metA starts at AUG2, but requires the SD in the riboswitch. A) Schematic representation of the metA regions cloned in the indicated plasmids, which harbour translational egfp fusions. B) Relative fluorescence of TY and MM cultures of S. meliloti 2011 strains carrying the indicated plasmids. The graph shows means of three independent experiments and single measure points representing means from three technical replicates of each independent experiment; n.s.: not significant. C) Schematic representation of the pCD33-egfp plasmid and the used mutations (indicated at the RNA level). For other details, see Figure 4A and Figure 1A. D) Predicted secondary structure of the riboswitch in its SAM-bound form (compare to Figure 1B). Shown are the mutations used in the pCD33-AUG1m-egfp and pCD33-SDm-egfp plasmids.