FIGURE 7.

Nucleotides affected by the SRL deletion are widely distributed in the 23S rRNA secondary structure, but localized within and around the functional core of the 50S subunit. (A) Secondary structure of 23S rRNA indicating nucleotides in ΔSRL 50S subunits that show strongly enhanced (●), weakly enhanced (∙), or reduced (○) reactivity to structure probes; the SRL (h95) is indicated in red. (B) 23S rRNA regions highlighted in A (dark black line) were mapped onto the 50S subunit of the E. coli ribosome crystal structure (Schuwirth et al. 2005), and are shown in dark blue. Protein L16 (pink), 23S rRNA helix 95 (yellow), and the SRL (red) are indicated; other ribosomal proteins are light blue and 5S and 23S rRNA are gray. P-site (orange) and A-site (yellow) tRNAs were docked onto the structure using coordinates from Yusupov et al. (2001) and Korostelev et al. (2006).