Degradation of rRNA during starvation. (A) WT and RNase II− cells were first grown in M9/glucose at 31°C to an A600 of ∼0.2 and then either starved of glucose for 4 h (−g) or grown in the presence of glucose for 4 h (+g) at 42°C, as described in Materials and Methods. Cells were collected by centrifugation, and total RNA was extracted and resolved by Synergel/agarose gel electrophoresis, as described in Materials and Methods. The gel was stained with ethidium bromide and visualized by UV irradiation. (B) RNase II− or RNase II− RNase PH− cells were first grown in M9/glucose at 31°C to early exponential phase (zero time) and then starved of glucose for an additional 4 h (−glucose) at either 42°C or 31°C. Total RNA was extracted and resolved by Synergel/agarose gel electrophoresis followed by ethidium bromide staining.
