Transfer RNAs Mediate the Rapid Adaptation of Escherichia coli to Oxidative Stress
The tRNAs are displayed in alphabetical order and named according to their amino acids and anticodons. (A) Decreased tRNA levels following 15 min of H2O2-induced oxidative stress, relative to tRNA levels observed under normal conditions. The data were generated by next-generation sequencing. (B) qRT-PCR validation of the tRNA decreases induced by 15 min of oxidative stress, using independent biological replicates. The data are shown as the mean ± SD. (C) Decreased tRNA levels following 30 min of OS, measured by next-generation sequencing. (D) Agarose gel electrophoresis of the total RNA extracted from the same number of cells grown under normal conditions (N) or under 15 min of oxidative stress (OS). (E) Polyacrylamide gel electrophoresis of the sample represented in panel (D) to resolve the tRNAs. The size range of tRNAs is indicated. (F) Growth curves before and after the application of oxidative stress. The red line shows the moving average of the OD635 observed over 5 min. (G) The tRNA concentration after 90 min of oxidative stress, after which the bacteria had fully adapted to the stress and growth was resumed. (H) qRT-PCR validation of the results shown in panel (G), using an independent biological replicate. The data are shown as the mean ± SD.