Transfer RNAs Mediate the Rapid Adaptation of Escherichia coli to Oxidative Stress

PLoS Genet. 2015 Jun 19;11(6):e1005302. doi: 10.1371/journal.pgen.1005302. eCollection 2015 Jun.

Abstract

Translational systems can respond promptly to sudden environmental changes to provide rapid adaptations to environmental stress. Unlike the well-studied translational responses to oxidative stress in eukaryotic systems, little is known regarding how prokaryotes respond rapidly to oxidative stress in terms of translation. In this study, we measured protein synthesis from the entire Escherichia coli proteome and found that protein synthesis was severely slowed down under oxidative stress. With unchanged translation initiation, this slowdown was caused by decreased translation elongation speed. We further confirmed by tRNA sequencing and qRT-PCR that this deceleration was caused by a global, enzymatic downregulation of almost all tRNA species shortly after exposure to oxidative agents. Elevation in tRNA levels accelerated translation and protected E. coli against oxidative stress caused by hydrogen peroxide and the antibiotic ciprofloxacin. Our results showed that the global regulation of tRNAs mediates the rapid adjustment of the E. coli translation system for prompt adaptation to oxidative stress.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adaptation, Physiological*
  • Down-Regulation
  • Escherichia coli / genetics
  • Escherichia coli / metabolism*
  • Oxidative Stress*
  • RNA, Transfer / genetics
  • RNA, Transfer / metabolism*

Substances

  • RNA, Transfer

Associated data

  • GEO/GSE62995

Grant support

This work was collectively supported by the National Natural Science Foundation of China (81322028 and 31300649), National High-Tech Research and Development Program (863) of China (2014AA020504), the National "973" Projects of China (2011CB910700) and the Key Project of the Chinese Ministry of Education (212207). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.