Isolation and Quantification of Radiolabeled rRNA

We followed the RNAsnap procedure (46 (link)) to isolate rRNA from ³²P labelled exponential cultures (OD₆₀₀ approximately 0.3) grown at 37°C. The rRNA samples were precipitated out via ethanol reprecipitation (0.1 × 5 M NaCl and 2× ethanol were added to 1× volume of rRNA sample and mixed vigorously by vortexing. The samples were then spun down at 16 000g for 5 min, and the supernatant was completely removed via aspiration and the pellet was resuspended in TE) prior to running them on a 1.1% agarose gel at 60 V for 2 h. After the run, the gel was dried and exposed to a PhosphorImager screen. The resulting signals were measured with a PhosphorImager (Fuji Film FLA-3000).